Divisor 28691

To determine if any number is divisible by 28691, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 13 and 2207 - then it is divisible by 28691.

The following tests must pass:

• Test if a number is divisible by 13
• The "Stef Siekman Test" for Divisibility by 2207

Easy!