Selena Gomez Serenaded by Dozens of Celebrities on 20th Birthday

It'll be hard to top Selena Gomez's 20th birthday.

The "Hit the Lights" singer, who looked radiant in a Dsquared2 dress and Herve Leger heels, was serenaded by dozens of celebrities -- including Taylor Swift, 22, Josh Hutcherson, 19, Ellen DeGeneres, 54, Zooey Deschanel, 32, and Jonah Hill, 28 -- after collecting a surfboard for Choice Music Group at the Teen Choice Awards in Universal City, Calif., on July 22.

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As the star-studded crowd sang "Happy Birthday," Gomez blew out sparkler-topped cupcakes, which she later shared with audience members. "This is the best birthday present ever," Gomez told those gathered at the Gibson Amphitheater in Los Angeles.

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Later in the show, an eyewitness spotted Gomez and Swift "bobbing their heads" as the "Wizards of Waverly Place" star's boyfriend, Justin Bieber, 18, performed a medley of "Boyfriend" and "As Long as You Love Me."

Post-show, Gomez and Bieber had a romantic dinner at Il Cielo in Beverly Hills, Calif. "Selena walked out the front holding hands with Justin and she was holding a bouquet of flowers," a source tells Us Weekly.

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On July 23, Gomez raved about her unforgettable day via Facebook. "Beyond blessed. So much love," she wrote. "Thank you for the most incredible birthday yet! I'm truly, truly grateful. I love my family, friends and all of you."

This article originally appeared on Usmagazine.com: Selena Gomez Serenaded by Dozens of Celebrities on 20th Birthday

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