17. Troye Sivan: 21 Under 21 (2014)

21 Under 21 Main Page

Birthdate: June 5, 1995 (Age: 19)

Last Year's Rank: N/A

Why He's Hot: You might recognize rising Australian/South African star Troye Sivan from YouTube, where his channel has over 2.7 million subscribers, or from the movies, where he played a young Wolverine in X-Men Origins: Wolverine. And by now, you may also be familiar with his budding music career. After years of singing covers on YouTube, the soulful Sivan released his major label debut EP TRXYE in 2014, which reached No. 5 on the Billboard 200. Forget teen pop: since signing with EMI, Sivan has pursued a sonically adventurous brand of ambient pop that's more indebted to James Blake than Justin Timberlake. This is Sivan's first year on Billboard's 21 Under 21, and if the momentum keeps up, it certainly won’t be his last.

21 Under 21's Next Class | Top 21 Songs by Under-21 Singers 

Billboard's 2014 21 Under 21 List