##  [Euler's Totient Function](/index.php/eulers-totient-function) 

  ##  [Euler's Totient Function](https://puremath.quantumdictionary.io/eulers-totient-function-0) 

  

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**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

Arithmetic function φ(n) that counts the positive integers up to n that are coprime to n; equivalently, the order of the multiplicative group of units modulo n.