Divisor 19331

To determine if any number is divisible by 19331, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 13 and 1487 - then it is divisible by 19331.

The following tests must pass:

• Test if a number is divisible by 13
• The "Kathryn Castellana Test" for Divisibility by 1487

Easy!