Divisor 15625

To determine if any number is divisible by 15625, apply this test:

1. Ignore everything except the 6 right-most digits. Every larger digit than these is irrelevant because 10⁶ is divisible by 15625.
2. The number should now be small enough to be able to deduce divisibility by 15625 with basic application of your 15625-times tables!

Easy!