If the last 4 digits are divisible by 80, the entire number is divisible by 80.
But really, it is hardly worth-while to learn divisibility rules for a large amount of numbers; only for a few small numbers. Normally it is easier to just do the division.
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Those for 1, 2, 4, 5 and 8.
A number is a multiple of 312 if it's a multiple of 3, 8 and 13 at the same time
Knowing the divisibility rules will help you by being able to recognize if a number has factors (other than one and itself) which are covered by the rules. This will save actually having to start doing divisions.
If the number is even and the sum of its digits is divisible by nine then the number is divisible by 18.
If the rules for 2 and 3 work, the number is divisibale by 5.