Divisor 27781

To determine if any number is divisible by 27781, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 13 and 2137 - then it is divisible by 27781.

The following tests must pass:

• Test if a number is divisible by 13
• The "Paolo Ricciuti Test" for Divisibility by 2137

Easy!