Numbers {perfect number} can equal sum of prime factors: 6 = 1 + 2 + 3. If 2^n - 1 is prime number and n is integer, 2^(n - 1) * (2^n - 1) is perfect number. Number's prime-factor sum can be greater than number {deficient number} {defective number}. Number's prime-factor sum can be less than number {abundant number} {excessive number} {redundant number}.
Mathematical Sciences>Number Theory>Number Types
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Date Modified: 2022.0224