A 6-digit number has digits as consecutive natural numbers. The number is always divisible by

Consider a 6-digit number of the form XYXYXY. The number is divisible by :

Find the sum of all three-digit numbers divisible by 9.

The number 97^30 - 14^30 is divisible by:

How many three-digit numbers are divisible by 5?

Let m and n be natural numbers. What is the minimum value of (m + n) such that 33m + 22n is divisible by 121?