Euler Phi Function of 95

Example of Euler $\phi$ Function of Non-Square Semiprime

$\phi \left({95}\right) = 72$

where $\phi$ denotes the Euler $\phi$ Function.

Proof

We have that:

$91 = 5 \times 19$

Thus:

\(\ds \phi \left({95}\right)\)

\(=\)

\(\ds \left({5 - 1}\right) \left({19 - 1}\right)\)

Euler $\phi$ Function of Non-Square Semiprime

\(\ds \)

\(=\)

\(\ds 4 \times 18\)

\(\ds \)

\(=\)

\(\ds 72\)

$\blacksquare$