Divisor 1631

To determine if any number is divisible by 1631, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 7 and 233 - then it is divisible by 1631.

The following tests must pass:

• Test if a number is divisible by 7
• Test if a number is divisible by 233

Easy!