How are numbers encrypted in Caesar Cipher?

Question

Is my guess right?
Input : 30
Output : 52 (with a shift of two)

Answer 1

Typically there is no standard for Caesar shifting beyond the letters of the alphabet, but according to a StackExchange post I saw you can do what you like, like say, extend the letters of the alphabet with special characters and yes, numbers, and do the Caesar shift over the whole thing. Meaning "y"->"2" possibly.