This number is a prime.
Called the Whovian number, this prime is related to the longest running science fiction TV series, Dr. Who. It is the air time and date for the first Doctor Who episode on BBC (signifying 17:16 23 November 1963). It also happens to be the activation code of the Vortex Manipulator, as briefly glimpsed when the Doctor scratches the numbers into the cell wall. [Forouhari]