Divisor 21287

To determine if any number is divisible by 21287, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 7 and 3041 - then it is divisible by 21287.

The following tests must pass:

• Test if a number is divisible by 7
• The "Killianjune Test" for Divisibility by 3041

Easy!