Divisor 16521

To determine if any number is divisible by 16521, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 3 and 5507 - then it is divisible by 16521.

The following tests must pass:

• Test if a number is divisible by 3
• The "Angus Cos Test" for Divisibility by 5507

Easy!