Divisor 16221

To determine if any number is divisible by 16221, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 3 and 5407 - then it is divisible by 16221.

The following tests must pass:

• Test if a number is divisible by 3
• The "Phil Test" for Divisibility by 5407

Easy!