Divisor 20783

To determine if any number is divisible by 20783, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 7 and 2969 - then it is divisible by 20783.

The following tests must pass:

• Test if a number is divisible by 7
• The "Brad Test" for Divisibility by 2969

Easy!