655321 is the prisoner number of Alex in A Clockwork Orange by Anthony Burgess, subsequently adapted into a 1971 film by Stanley Kubrick.
It may also refer to: The prisoner number of Zorak in "Time Machine", a 2001 episode of The Brak Show A song on the 2005 album We're Already Gone by roots music group the Beautiful Girls The employee number of Nolan Sorrento in the 2011 science fiction novel Ready Player One The prisoner number of Plankton in "Jailbreak", a 2013 episode of SpongeBob SquarePants The candidate reference number of Skeletor in the 2018 dystopian action horror film The First Purge