Understanding the Sigma Function: Divisors, Multiplicativity, and the Formula Understanding the Sigma Function: From Divisors to a Powerful Closed Formula Why the Sigma Function Is Multiplicative: A Step-by-Step Derivation The Mathematics Behind σ(n): Divisors, Prime Powers, and the Product Formula A Deep Dive Into the Sum-of-Divisors Function (σ): Theory + Python Code Decoding σ(n): The Elegant…