Unless something really unexpected develops, Believe Acoustic will be your fifth No. 1 album. No one in the 55-plus-year history of our charts has accomplished this at your age. How do you wrap your head around this? Is the history important to you?

Of course. I feel blessed that I'm able to do what I love for a living. I can support my family. I grew up without a lot. I remember ordering food off the menu with my mom and we'd have to share because we couldn't afford more. I love performing. When I go onstage and I see these people? That's what I do it for.

But as you start to climb some of these Mount Rushmore-type accomplishments--like most No. 1 albums for an 18-year-old, something that even some of the greats that started young like Stevie Wonder never did--it must be a lot to process.

To look at all of these greats and see that I have stats that are kind of equivalent to what they've done? It's amazing to wrap my head around that because I look up to these people so much: Michael Jackson, Stevie Wonder, Prince, Boyz 2 Men...soul and R&B, that's what I grew up listening to.

Is a No. 1 album a validation?

Definitely. It shows that I'm still making good music and people are supporting me and I'm not going anywhere any time soon. This is just an acoustic album of an album that I've already put out and it's going to go No. 1--that shows people that I'm still here and that talent rises above everything else. There's so much going on. Talent rises above all of that.

Speaking of validation, let's talk about the Grammys. Your manager Scooter Braun took to Twitter when the nominations were announced and you didn't get one. How did you feel about it?

I felt the same way that Scooter felt, I just can't really...it's good that he can put it out there and say that. He had my back just like any manager would. My whole life I've dreamed of winning a Grammy. At this point, the excitement of that has gone down. I'm more excited to just make great music for my fans. That's just something that if it happens, it happens.

It's not about you disapproving of other artists.

No, of course not. I'm so happy for the other artists who got nominated and have won Grammys. I'm 18 and I think that I have a lot ahead of me, so I'm not worried.

Will you go to the Grammys this year?

I will not be there.

Is there anyone that you're pulling for that night?

Chris Brown. I'm a fan. His music is really good. That's what they should focus on: the music.

You have become the most-followed person on Twitter.

Yes! It's pretty awesome, because at every interview, people will be like, "So how many Twitter followers do you have?," and I'm like, "I'm second behind Lady Gaga." Now I'm No. 1, and it's cool to be able to say that.

You've been using Twitter to tease the arrival of the new album: "In X number of days people will know how I feel." Did you write "Nothing Like Us" thinking that it would be on the album?

No, I write all of the time in the studio. When I recorded it, I think the album was done. Scooter heard it and was like, "This is amazing. If I rush to get it on the acoustic album, would you want it on there?" I want people to hear what's coming from my heart, and this is definitely the most that I've been sharing what I'm actually feeling.

It's not quite what I expected. There's been all this back-and-forth with both you and Selena Gomez separately covering "Cry Me a River." The blogs have a field day speculating about what happened to your relationship.

There's so many rumors. People say I call Selena every day and she won't pick up the phone or I'm chasing her down, and these are all fake stories.

Do you pay attention?

I don't go on blogs or anything like that. I hear things. People tell me if something happens on the Internet. It gets back to me, definitely.

What was the writing process like for "Nothing Like Us"?

I was in L.A. at the Four Seasons, and they have a piano in the room. I sat down and it was something that came out, and I recorded it on my iPhone. Then I went to the studio and I really recorded it and sang it better.

Who do you work with? When you took that song into the studio, who's there?

Well, that was just me and Josh [Gudwin], who's my engineer. I need an engineer to work ProTools while I'm doing all of the guitar and singing.

Recently I was interviewed about the Grammys. We ran out of time and I lamented that we didn't get to talk about you not receiving nominations. The segment producer was like, "Oh, I can't stand Justin." I'm sure that it's not a secret to you that there are haters out there.

Of course.

She said it was because you were a pre-fab pop act who didn't play your own instruments or write your own songs and can't sing. Of course, you both play and write. And now with the acoustic album 

With Acoustic, it's just raw--me and a guitar. I'm not hiding behind any beats. I want people to hear that I'm getting older and my voice is getting stronger. If you really don't enjoy the type of music I make and that's not you, OK. But don't say I'm not talented. If you haven't noticed, I wasn't made--I was found.

Is it just that people reflexively try and tear down success?

Of course. People always help you get to the top and once you get there, all they try to do is bring you down. I focus on keeping my head up and paying attention to the people who are important to me, my family, and just making good music, proving them wrong. To be honest, I would still rather be the underdog, have more haters and people talking about me and have you defend me.

Listening to the new songs, it seems like it's been a wearying time for you. "Yellow Raincoat" has the line, "Fame, money and girls drive you crazy." And of course "Nothing Like Us," it's kind of heavy. Are you having fun?

Definitely, all of the time. I'm 18. I have a great team around me. I have great friends. We have a blast. They keep me occupied and my mind off of the negative things. It's funny when people are like, "You're 18. What have you really gone through?" I'm thinking, "What do you mean? When you were 18, you don't think that you went through stuff?" When you are 18, you're going through that transition. You have a high school girlfriend, you might not. Going to college. Figuring yourself out, leaving home.

That's one of the reasons that I like "Nothing Like Us." You manage to take this very real, young feeling and make it universal. I like that the song was sweet. Scooter told me you wrote it about what happened with Selena, but he didn't tell me what it sounded like. And if you read the blogs, you think it might be an angry song. Instead, it feels...

Because at the end of the day, there's nothing like us, you know? That's just it. It is what it is. People are going to relate to that.

You're pretty heartbroken?

I'm not in the happiest place that I've ever been. I'm trying to get through what I'm going through. Like I said, I have my really close friends to cheer me up and keep me going.

Have you ever listened to Off the Wall?

Yes, of course!

You know--"Out of My Life"...

Definitely--emotion, lots of emotion. That was one of the things that I admired in Michael--everything he sings, you feel the depth and the emotion. The ends of his sentences, the different noises he makes that accentuate what he's feeling. That's what I was doing with my song. I gave it my heart and I wanted it to feel what I'm feeling. I wasn't crying when I was singing, but I definitely got emotional.

How many instruments did you play on the original Believe?

Piano, guitar and drums.

It's been one of your most successful albums. That's got to feel good.

They say there's a sophomore slump. I didn't have one. It was really good to see it at the top. When I was going on all of these different talk shows when it was the No. 1 album of the year, just hearing that: No. 1 album of the year, Justin Bieber? That's a really great feeling.

On Believe, you wrote or co-wrote every song on that album?

Yeah, every song.

How many of them did you write fully?

I think four.

What's your favorite that you wrote yourself?

Probably "Be Alright." I was overseas, and I was missing my girlfriend and I was just worried about what I was feeling...I was over mountains, across the sky, just wanted to let her know that everything was going to be all right. That was actually just straight lyrics like a poem, on the plane. When I got there, I told [musical director] Dan [Kanter] what I wanted him to play and he played it. I just made the melody then.

What else has been memorable about Believe and Believe Acoustic?

This wasn't from my acoustic album, but from Believe. Bei Maejor is one of the most talented people to work with. We did "Love Me Like You Do" and "One Love." Besides that we've done a lot of new stuff...I'm not comparing it to Michael and Quincy [Jones], but we have a vibe together that works really well and I feel that we're going to be working together for a really long time...With everyone else, they would come in with ideas, things that were already done. Me and Bei always started from square one and I really respected him for that. He'd be like, "What are you feeling? Let's just work from there, make fun music that young people are going to love, but makes sense and has depth."

You're working on your next album essentially?

Either next album or for something to release through the Internet...I have so much on my mind, I want to put it in my music. I know I just put out Believe, and this acoustic album, but I want to produce music.

Do you ever think of a day when perhaps you won't be "hot right now"?

Yeah, of course. I don't think that I'm going to be boiling hot for the rest of my career. I think that, if I'm not on top...it would be because I didn't want to be. It would be a time when I wanted to take a break and do movies or take a break and raise a family. When I'm doing music and I'm really focused, I'm not going to not be where I am.

Have you thought about movies?

I don't want to be a movie star. [Justin] Timberlake is a movie star. It's been years since he put out a song. I won't take that long off. I might take a summer off to do a movie. There were a couple of movies that I really wanted to do, but they weren't right at the time. Movies, they're always sending me scripts, and I'm getting too old for certain scripts that they're sending me. I think I'm going to wait until next summer.

What kind of actor would you like to be?

I would say Ben Affleck. He can do comedy and be serious, but I wouldn't say he's a funny character...I don't have natural timing like Seth Rogen. He's just naturally funny. Jonah Hill, Will Farrell, you have to be that type of comedic person. But I definitely see me being the type of person who can deliver jokes.

We're going to find out, right?

Oh, yeah. "Saturday Night Live."

You're going to be performing and hosting. Did you have to have a conversation with Lorne Michaels about what you'll do?

I'm going to go early to rehearse and to talk to him about the scripts and see what I'm comfortable with and what they're comfortable with.

Is there anything that's off limits?

There's definitely some things that are off limits, as far as personal things. But, we're going to joke and make light of things. We're speaking now to figure out what's appropriate and what's funny. "Night at the Roxbury"? I want to redo that.

You mooned Instagram recently. People make a pretty big deal about things that lots of normal 18-year-olds do.

I'm glad you get that.

You did it on a Justin Bieber step-and-repeat. It seemed pretty clear to me that you weren't taking yourself so seriously.

That's what I was doing. I got so many people telling me, "You should take it down." I was just being silly. I thought my fans thought it was funny, but people didn't take it too well. I saw it on the news--"Justin Bieber flashes..."--and I was like, "Really? That's on the news? This is what you're worried about? There's people dying, and you're worried about me?"

When you look back over the last couple of years, is there anything you regret?

I don't have any regrets. I live and I learn. My mom says, "You got to learn the hard way, don't you?" That's me. I learn the hard way. But it's about how I pick myself up and be better and stronger.

What do you think are your biggest challenges in the years ahead?

Probably separating my business and personal life--you got to know when to take time for yourself, when to work. Even earlier, when you walked in, it wasn't me being disrespectful. You caught me off guard. If I'm always on everyone else's time, I'd go crazy...For a bit, I was really focused on my work, and every day I was working and tweeting, and I wasn't really talking to my friends. I was losing relationships with my family members. You got to realize what's important: Your family's important, and that's going to keep me sane and a good person...My dad called me the other day and he was like, "Really, Justin, you need a [purpose]. What are you doing this for? You got all of the money in the world. You got all of the fans in the world. You need to focus on why you're doing this and do it for you and do it for the right reasons." That was really good to hear.