Justin Bieber spent 4th of July weekend partying with Kourtney Kardashian, dancing to Rihanna and wakeboarding in his underwear

For a Canadian, Justin Bieber knows how to enjoy a wild Fourth of July weekend!

The "Sorry" singer celebrated restaurateur David Grutman's belated 36th birthday on Sunday evening, joining the club owner at his STORY nightclub in Miami, Florida.

Bieber hosted his Purpose World Tour after party at the club, and even sang a b-day song for Grutman, who shared his thanks (and a video of the performance) to Instagram.

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The 22-year-old singer also shared a short clip of the celebration from inside the DJ's booth as he danced and sang along to Rihanna's "Work."

One of Bieber's former rumored romantic interests was also in attendance at the party: Kourtney Kardashian, who was joined by friends Larsa Pippen and Jonathan Cheban. According to an eyewitness, Kardashian and Bieber spent some time hanging out and chatting in the DJ Booth during the festivities.

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Earlier that day, Bieber hung out in Miami Beach, where the pop star partook in some wild wakeboarding.

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Aside from his tighty-whities, the singer stayed (somewhat) safe in a neon-green life vest, and that's pretty much it. At least those Miami waters are warm this time of year.

Bieber wasn't the only celeb to spend the Independence Day weekend in style. Check out the video below for a look at how some stars celebrated the national holiday.