N o w - H o l l y w o o d . b l o g s p o t .c o m

After performing on Simon Cowell's X Factor on Saturday, Britney Spears dropped by British nightclub G-A-Y to celebrate her birthday a few days early.

Her pals surprised her with a cake decorated to look like the cover of her new album Circus and serenaded her with "Happy Birthday."

Spears is now heading to New York City to perform on Good Morning America on Tuesday -- her actual 27th birthday.

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