Divisor 20645

To determine if any number is divisible by 20645, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 5 and 4129 - then it is divisible by 20645.

The following tests must pass:

• Test if a number is divisible by 5
• The "Oscar Harris Test" for Divisibility by 4129

Easy!