Euler totient function - $|(Z/nZ)^*|=\phi(n)$
15000
Show that number of elements in $(Z/nZ)^*$ is $\phi (n)$
158582
Prove that $\{\frac{\phi (n)}{n}\}_{n \in \Bbb N}$ is dense in $[0,1]$
41141
Proving that $\frac{\phi^{400}+1}{\phi^{200}}$ is an integer.
136623
Hints/ Solution in finding a formula $\phi(n)$ for a binary square matrix
17316
If $a^\phi = 1$ then the order of $a$ divides $\phi$
117681
For which Natural $n\ge2: \phi(n)=n/2$
45127
Why is Euler's totient function equal to $(p-1)(q-1)$ when $N=pq$ and $p$ and $q$ are prime in a clean intuitive way?
58188
What's the proof that the Euler totient function is multiplicative?
60284
Infinitely many positive integers $n$ such that $\phi(n) = \frac{n}{4}$?
105943
Laurent series for $1/(e^z-1)$
29531
A Question On Euler's Proof Of the Basel Problem
78342
When is $\phi(n)$ a prime number?
57416
Fibonacci identity: $f_{n-1}f_{n+1} - f_{n}^2 = (-1)^n$
115258
Find all positive integers $n$ such that $\phi(n)+\sigma(n)=2n$.
80670
'Lines' in the Euler phi graph
82448
Why is $f(x) = x\phi(x)$ one-to-one?
142931
Problem on Euler's Phi function