Justin Bieber is Feeling Nostalgic About His 'My World' Album

Justin Bieber listens to his old music every now and then, it seems.

The 23-year-old singer took to Instagram where he posted a photo of his song “Common Denominator,” which if you remember, appeared as a bonus track on his debut album My World back in 2009.

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We’re not exactly sure why he posted it, but maybe he was just feeling a little nostalgic!

Pictured: Justin is all smiles while leaving Warwick nightclub with some friends on Thursday night (July 19) in West Hollywood, Calif.