Okay, I see everyone went with numbers featured in the title so I am going to post examples to demonstrate better what I meant:
42
237 (This one counts double)
24601
No more ideas.
I refrain from 7 because that one has been used ad nauseam, so much so that it has become a cliché, however much one might like Se7en. 13 also goes into that category, though arguably movies such as 13th that use it in different ways are not cliché.