Euler phi function proof
4972
Mod of numbers with large exponents [modular order reduction]
68385
Prove that $ \frac{n}{\phi(n)} = \sum\limits_{d \mid n} \frac{\mu^2(d)}{\phi(d)} $
125188
how to prove $m^{\phi(n)}+n^{\phi(m)}\equiv 1 \pmod{mn}$ where m and n are relatively prime?
157711
Number Theory: Prove that $m | \phi(a^m - 1)$
119118
Prove $n\mid \phi(2^n-1)$
140249
Euler Product formula for Riemann zeta function proof
92359
Big-O Notation Proof
47790
If $x \geq 2$ prove that $\sum_{ n \leq x} \frac{1}{\phi(n)} = \mathcal{O}(\log(x))$
152084
Binomial-Theorem proof
84930
How to justify $\phi(n) \ge \sqrt{n}$
80670
'Lines' in the Euler phi graph
35313
Proof of Euclid's Lemma
91889
Prove $\phi^n = \phi F_n + \text{(another Fibonacci number)}$ using mathematical induction.
158582
Prove that $\{\frac{\phi (n)}{n}\}_{n \in \Bbb N}$ is dense in $[0,1]$
742
How to prove Euler's formula: $e^{i\varphi}=\cos(\varphi) +i\sin(\varphi)$?
46065
How do you find all $n$ such that $\phi(n)|n$
58188
What's the proof that the Euler totient function is multiplicative?