Divisor 21907

To determine if any number is divisible by 21907, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 19 and 1153 - then it is divisible by 21907.

The following tests must pass:

• Test if a number is divisible by 19
• The "Guillaume Lederrey Test" for Divisibility by 1153

Easy!