Test of divisibility of 3, 9, 27, 37, 111, 333 or 999

Find test of divisibility of 9138431772

Step 1 Make groups of 3 digits from the end groups are as 9 138 431 772

Step 2 add all groups 9 + 138 + 431 + 772 = 1350

Step 3 Repeat same steps 1 and 2 it is 1 + 350 = 351 = 333 + 18

333 is divisible by 37 but 18 is not so 9138431772 is not divisible by 37

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