Chris Brown -- Listening Party Attracts Huge Celebs ... And a Curious One

11:01 AM PT: Sources tell TMZ ... Scott showed up for a few hours but was NOT drinking while he was at the club.

Chris Brown had a hugely successful listening party for his new album "Royalty" ... and Scott Disick was right in the middle of it.

A slew of people were front and center at Hyde on the Sunset Strip ... Usher, French Montana, Kendall Jenner, Andre Berto, Big Boy and lots of others.

Scott's presence was a little weird ... it was turnt up for sure, and Scott just got out of rehab.

BTW, "Royalty" drops December 18.