Singer Katy Perry, who just released her electronica-inflected album “Witness,” has become the first Twitter user to reach 100 million followers.

Perry joined Twitter in February 2009, reaching 50 million followers on @katyperry by mid-2012. The second most-followed Twitter account belongs to Justin Bieber, who currently has 96.7 million followers. Next in line are Barack Obama (90.8 million), Taylor Swift (85.1 million) and Rihanna (74.1 million).

Of course, how many millions of those followers are actually spam accounts or bots is unclear. CEO Jack Dorsey told Wall Street analysts in April that Twitter is continuing to battle bogus bots, which he said make up less than 5% of accounts.

Twitter congratulated Perry on reaching the milestone with a retrospective video of her tweets over the years

"Today, we #WITNESS history. Congratulations @katyperry, the first to reach 100 million followers! #LoveKaty"