20 Things You Didn't Know About Inception
12. Recurring Numbers
528491. You definitely recognize these numbers from a few scenes, but they appeared more than you may have noticed.
528491 are random digits that Fischer gives the team in his mind, and they appear a frequently for the rest of the movie.
528-491 is the "phone number" that Eames (disguised as a blond woman) gives to Fischer in the hotel dream. Also, the hotel room where the team falls asleep in is room 528, and the room below them where Arthur plants the explosives is, you guessed it, room 491. Finally, these numbers are what Fischer ultimately creates as the combination to the safe wherein his subconscious hides his secrets.
These aren't the only numbers that recur in the film, though. The numbers 2053 appear on the back of the taxicab that the team pick up Fischer in, while a variation of those numbers, 3502, appear on the front of the train that comes straight out of nowhere.
Whatever the meaning of those numbers are is anyone's guess.