Divisor 1971

To determine if any number is divisible by 1971, you must apply 2 tests successively. If all of them 'pass' - that is, if your number is divisible by 27 and 73 - then it is divisible by 1971.

The following tests must pass:

• Test if a number is divisible by 27
• Test if a number is divisible by 73

Easy!