Kim Kardashian
isn't the only star tweeting sexy bikini photos of herself.

Britney Spears posted this photo of herself in a floral two-piece with the caption "having some fun in the sun... don't want summer to be over!"

Judging by her golden tan and sun-kissed waves, the 30-year-old pop star has been enjoying her time in the sun. She should enjoy it, since "The X Factor" is premiering on September 12th and she'll be doing a lot of promotion for it.

Britney's followers have been complimenting her on the photo, including on famous fan.

An impressed will.i.am tweeted, "OMG...You're looking fit and hot. Can't wait to shoot the video to our song. Your fans are gonna love it."

For even more toned tummies, check out our gallery of the hottest celebrity beach bodies, above!

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