Divisor 25909

To determine if any number is divisible by 25909, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 13 and 1993 - then it is divisible by 25909.

The following tests must pass:

• Test if a number is divisible by 13
• The "Bendik Vatne Test" for Divisibility by 1993

Easy!