Interesting Things with JC 1211: "3425" - What if a simple number wasn’t so simple? 3425 is a semi-prime with cryptographic significance, a number that changes properties when reversed, and one that has surfaced in digital security and code breaking methods. From encryption to historical transmissions, 3425 may be more than just four digits.

Ref - Weisstein, E. W. (n.d.). Semiprime. In MathWorld – A Wolfram Web Resource. Retrieved from https://mathworld.wolfram.com/Semiprime.html