This is documentation for Mathematica 3, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.2)
 Documentation / Mathematica / Built-in Functions / Mathematical Functions / Number Theory  /
EulerPhi

  • EulerPhi[ n ] gives the Euler totient function .
  • Integer mathematical function (see Section A.3.10).
  • gives the number of positive integers less than which are relatively prime to .
  • See the Mathematica book: Section 3.2.4.
  • See also: FactorInteger, Divisors, MoebiusMu.

    Further Examples

    Up to 10 there are four numbers relatively prime to 10.

    In[1]:=

    Out[1]=

    In[2]:=

    Out[2]=