Number of divisors/factors of the number
Let the number be n = a^m * b^n * c^p
(where a, b, and c are n's prime divisors and m,n, and p are the number of times that divisor is repeated) then the total count for all of the divisors is (m + 1) * (n + 1) * (p + 1).
Sum of factors
Sum = (a 0 + a1 + ...+a m-1)(b 0 + b1 + ...+b n-1)(c 0 + c1 + ...+c p-1)
i.e.
= (am+1 - 1)/(a-1) * (b n+1 - 1) / (b-1) *(c p+1 - 1)/ (c-1)
Let the number be n = a^m * b^n * c^p
(where a, b, and c are n's prime divisors and m,n, and p are the number of times that divisor is repeated) then the total count for all of the divisors is (m + 1) * (n + 1) * (p + 1).
Sum of factors
Sum = (a 0 + a1 + ...+a m-1)(b 0 + b1 + ...+b n-1)(c 0 + c1 + ...+c p-1)
i.e.
= (am+1 - 1)/(a-1) * (b n+1 - 1) / (b-1) *(c p+1 - 1)/ (c-1)
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