Factor sum calculator σ(n)
Calculate σ(n) — the sum of all positive divisors of n. This determines if a number is perfect, abundant, or deficient.
Number
Sum of divisors function
σ(n) adds up ALL positive divisors of n including 1 and n itself. σ(12) = 1+2+3+4+6+12 = 28.
Classification
Perfect: σ(n) = 2n (e.g. σ(6) = 12 = 2×6). Abundant: σ(n) > 2n. Deficient: σ(n) < 2n.
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