How many twitter followers do our most loved celebs have. Britney Spears was the 6th person to hit the 10 million twitter mark. Other celebs ringing in the followers, Justin Bieber, Lady Gaga, and Katy Perry and Kim K. Something I found rather interesting. That number of followers is the same number of people that populate Belgium!! Why we love our celebs? Because they are “professional celebrities of the entertainment world”- Mills.