Selena Gomez  turned 21 Monday, and there was no shortage of celebrations for her big birthday all week long. Selena rang in the special day with her closest pals, including her Spring Breakers costar Ashley Benson, over dinner, drinks, and, of course, birthday cake at swanky Bagatelle restaurant in LA. She and Ashley took to their Instagram accounts to document all the fun surrounding the occasion. Selena continued to celebrate her huge blowout on Tuesday, with a round of mimosas while stopping by at On Air With Ryan Seacrest  in the morning, and a guest performance on The Tonight Show With Jay Leno  in the evening.
Selena had much more than just her legal age to celebrate since her new album, Stars Dance, was released earlier this week, and immediately shot to the No. 1 spot on iTunes following its midnight release. One of the songs on her new album is appropriately titled "Birthday," and Selena shared photos from the music video she shot in honor of her own special day on her Instagram as well. Her pal Ashley not only showed her support while celebrating Selena's birthday, but also shared a picture of all of their friends at the birthday dinner holding up a number one, referring to Selena's album news with the caption, "And she beat Jay Z. Number one baby." Check out all the birthday fun from the entire week!
— Additional reporting by Ryan Roschke
Selena Gomez  posed at a dinner table with her friends, including Ashley Benson, for her 21st birthday party.
Selena Gomez  posted a picture from her music video for "Birthday."
Selena Gomez  and Ashley Benson cuddled up to their friends during Selena's 21st birthday celebrations.
Selena Gomez  gathered around her 21st birthday cake with her friends.
Selena Gomez  showed skin in a white crop top and tiny shorts to ring in her 21st birthday with friends.
Selena Gomez  had fun celebrating her birthday while filming the music video for her new song "Birthday."
Selena Gomez  shared a photo of her friends partying while she recorded a video for her song "Birthday" on her new album.
Ashley Benson shared a photo of her celebrating with Selena Gomez .
Selena Gomez  was excited that her birthday cake was made of Jack in the Box tacos.
Selena snapped a picture with Glee actor Chord Overstreet and Lily Collins.
Selena Gomez  performed a song on The Tonight Show With Jay Leno  on Tuesday evening.
Selena Gomez  drank mimosas on Tuesday morning during On Air With Ryan Seacrest .
Selena Gomez  posed with Lily Collins and Julianne Hough.
Ashley Benson and Selena Gomez  got a little goofy together.