Divisor 15777

To determine if any number is divisible by 15777, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 9 and 1753 - then it is divisible by 15777.

The following tests must pass:

• Test if a number is divisible by 9
• The "William Stone Test" for Divisibility by 1753

Easy!