Some time early Tuesday morning (June 18), Rihanna passed Justin Bieber as the most-viewed artist on YouTube. The 77 videos on Rihanna's official VEVO channel now have a combined 3.784 billion views in total, surpassing the total view counts of the 79 videos on Bieber's official VEVO channel by roughly two million views.
Rihanna surpassing Bieber's popularity on YouTube is largely due to the size of her subscriber base. Rihanna has 8.73 million subscribers on the platform, 3.7 million more than Bieber's 4.9 million. This means that while the average Bieber fan is much more engaged than Rihanna's, Rihanna has much broader reach as an artist and is therefore able to secure more view counts to her name over time.