Examples for

Number Theoretic Functions

A number theoretic function, or an arithmetic function, is a function that operates upon the domain of counting numbers. Such functions are important to number theory and other areas of mathematics. Examples of them include Euler's totient function, the Möbius function and the Carmichael function. Wolfram|Alpha has built-in knowledge of many number theoretical functions.
Functions

Learn about or utilize various number theoretic functions.

Get information about a number theoretic function:

Euler phi
sigma_2(n)

Do computations with number theoretic functions:

mu(30)
phi(110)
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