Divisor 10423

To determine if any number is divisible by 10423, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 7 and 1489 - then it is divisible by 10423.

The following tests must pass:

• Test if a number is divisible by 7
• The "Christopher Test" for Divisibility by 1489

Easy!