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

Justin Bieber's 4th of July: Partying with Kourtney Kardashian, 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.

PHOTOS: How Patriotic! Celebs Celebrate 4th of July

See more photos of Justin Bieber through the years:

The Evolution of Justin Bieber
See Gallery
The Evolution of Justin Bieber
Canadian pop megastar Justin Bieber (C) plays basketball with a young survivor of Super Typhoon Haiyan in Palo, Leyte province on December 10, 2013. Pop megastar Justin Bieber sang to and played basketball with young survivors of the Philippines' deadliest typhoon on December 10 after he flew into the disaster zone to boost an international relief effort. AFP PHOTO (Photo credit should read STR/AFP/Getty Images)
LOS ANGELES, CA - JULY 27: The winner of Champ of Charity singer Justin Bieber (L) and singer Cody Simpson onstage at the 2014 Young Hollywood Awards brought to you by Samsung Galaxy at The Wiltern on July 27, 2014 in Los Angeles, California. The Young Hollywood Awards will air on Monday, July 28 8/7c on The CW. (Photo by Frederick M. Brown/Getty Images for Variety)
The "Baby" singer headed straight to the salon for a new makeover ... this time going blonde! (Instagram)
LOS ANGELES, CA - AUGUST 23: Justin Bieber attends a VMA Pre-Party hosted by Chris Brown & Pia Mia featuring Bera on August 23, 2014 in Los Angeles, California. (Photo by Araya Diaz/Getty Images)
NEW YORK, NY - JAN 17: General view of a Justin Bieber for Calvin Klein Billboard located on Houston Street on January 17, 2015 in New York City. (Photo by Tomas/IMAGES/Getty Images)
LAS VEGAS, NV - MARCH 15: Singer Justin Bieber arrives at Omnia Nightclub at Caesars Palace to celebrate his birthday on the nightclub's opening weekend on March 15, 2015 in Las Vegas, Nevada. (Photo by Gabe Ginsberg/Getty Images)
CANNES, FRANCE - NOVEMBER 07: Singer Justin Bieber attends the 17th NRJ Music Awards ceremony at Palais des Festivals on November 7, 2015 in Cannes, France. (Photo by Marc Piasecki/WireImage)
LOS ANGELES, CA - JANUARY 18: Justin Bieber and Corey Gamble are seen in Beverly Hills, Ca on January 18, 2016 in Los Angeles, California. (Photo by Light Brigade/Bauer-Griffin/GC Images)

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.

WATCH: Justin Bieber Finally Addresses Those Kourtney Kardashian Hookup Rumors

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

WATCH: Celebrities Enjoy Independence Day Weekend With Loved Ones, Friends and Patriotic Pride

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.

Taylor Swift Hits the Beach With Tom Hiddleston at Fourth of July Party -- See the Pics!

Read Full Story

From Our Partners