A function f(m) is called multiplicative if (m, m') = 1 (i.e., the statement that m and m' are relatively prime) implies f(m m') = f(m) f(m') (Wilf 1994, p. 58). Examples of multiplicative functions are the Möbius function and totient function.

completely multiplicative function | Möbius function | multiplicative number theoretic function | quadratic residue | totient function