Divisor 21427

To determine if any number is divisible by 21427, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 7 and 3061 - then it is divisible by 21427.

The following tests must pass:

• Test if a number is divisible by 7
• The "Ryuto Inoue Test" for Divisibility by 3061

Easy!