The prime factors of 57 are 1, 3, 19, and 57. The prime factors are...
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rules of divisibility by 3: if the sum of the digits is divisible by 3, so is the number 5 + 7 = 12, therefore 57 is divisible by 3 57 / 3 = 19 therefore the factors are: 1, 3, 19
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32: 2 4 8 16 24: 2 3 4 6 8 12 40: 2 4 5 8 10 20 57: 3 19
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