Divisor 25689

To determine if any number is divisible by 25689, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 3 and 8563 - then it is divisible by 25689.

The following tests must pass:

• Test if a number is divisible by 3
• The "Roger Lüber Test" for Divisibility by 8563

Easy!