Euler's totient function

== English == === Etymology === Named after Swiss mathematician Leonhard Euler (1707–1783). === Proper noun === Euler's totient function (number theory) The function that calculates the total number of integers below a given integer that are coprime to it. ==== Usage notes ==== Usually denoted with the Greek letter phi ( ϕ {\displaystyle \phi } or φ {\displaystyle \varphi } ). ==== Related terms ==== Euler's formula ==== Translations ==== === Further reading === Euler's totient function on Wikipedia.Wikipedia