In movies, specially those that want to deal with Big Ideas, from end of the World to Aliens contacting us, etc. they always use Prime Numbers as the basis for the Big event.
So my question is, what is the significance of Prime Numbers beside the fact that they are divisible by themselves and 1 only?

Put another way, in what practical way are Prime Numbers highly useful, and thus significant? Again beside the fact that they are divisible by themselves and 1 only.

Curious Minds want 2 Know :)