New posts in Totient Function

How to calculate these totient summation sums efficiently?

Modified Euler's Totient function for counting constellations in reduced residue systems

Is the Euler phi function bounded below?

Values taken by Euler's phi function

inversion of the Euler totient function

Is there a direct, elementary proof of $n = \sum_{k|n} \phi(k)$?

What's the proof that the Euler totient function is multiplicative?

Prove if $n$ has a primitive root, then it has exactly $\phi(\phi(n))$ of them

If $a^\phi = 1$ then the order of $a$ divides $\phi$

Proving formula involving Euler's totient function