There is no doubt about it, Rihanna is one of the music world's hottest stars at the moment so it is no wonder some of the world's A List turned out to help her celebrate her 23rd birthday!

Rihanna spent the early part of her birthday performing an AMAZING set at the NBA All-Star Game in Los Angeles (if you missed it, check it out here).

People reports that after performing she headed to a private home in Beverly Hills where she grabbed a red velvet cupcake, exclaiming “I'm so hungry” before scooting off to a room with her BFF's.

After returning to the party in a tight-fitting pink dress, a source revealed: "She [gave] Ryan Phillippe and Zac Efron huge hugs."

According to the mag, the actors hung out together for most of the night and other high profile guests, Mary J Blige and Jay-Z were "laughing and having a blast" as they posed for photos in a corner.

Other guests included P Diddy, Christina Millan, Joel Madden and Snoop Dogg. Not a bad turn out!

Happy birthday RiRi!