Selena Gomez celebrated her 21st birthday at Bagatelle in Hollywood last night, and pals like Ashley Benson and Francia Raisa helped her blow out the candles and party the night away.

"Thank you to bagatellela for an amazing bday!!!! It's a birthday WEEK! #werk #becauseIcan," Selena tweeted. Ashley posted the top shot and wrote, "And she beat jay z number one baby," after learning that Selena's new single "Stars Dance" had snagged the number one spot on the charts. What a sweet way to spend a milestone birthday!

Gomez recently told Ryan Seacrest that she's been able to stay out of trouble by surrounding herself with an amazing group of friends. "At the end of the day, success is nothing if you don't have the right people to share it with," she said. "You're just going to end up lonely." Justin Bieber's ex-girlfriend said "it's fun" to go to Hollywood parties and "meet people" but added that she doesn't go out often. "I like my home a lot," she said. "Most of the time, I'm by the fire pit with friends." Well except last night ... looks like the former Disney darling let loose with a few drinks!

So was Bieber on her brain during the festivities? Selena says she's single, but we're wondering if he was able to sweep her off her feet with a sweet text...