Divisor 17801

To determine if any number is divisible by 17801, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 7 and 2543 - then it is divisible by 17801.

The following tests must pass:

• Test if a number is divisible by 7
• The "Christopher Bradfield Test" for Divisibility by 2543

Easy!