Divisor 20151

To determine if any number is divisible by 20151, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 9 and 2239 - then it is divisible by 20151.

The following tests must pass:

• Test if a number is divisible by 9
• The "Rafał Test" for Divisibility by 2239

Easy!