Divisor 21709

To determine if any number is divisible by 21709, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 17 and 1277 - then it is divisible by 21709.

The following tests must pass:

• Test if a number is divisible by 17
• The "ADC Test" for Divisibility by 1277

Easy!