Why do all prime numbers end with 1 3 7 9?

Excuse me, but could you elaborate on why it seems that all prime numbers end in the digits 1, 3, 7, or 9? Is there a mathematical principle or rule that governs this observation, or is it merely a coincidence that has arisen from examining a limited set of prime numbers? Furthermore, what implications does this trend, if any, have on the properties of prime numbers and their role in cryptography and other fields? I'm curious to understand the underlying reasons behind this intriguing pattern.