Calculate all $n \in \Bbb N \setminus \{41\}$ such that $\phi(n)=40$?
9753
How to solve the equation $\phi(n) = k$?
91451
find all positive integer $m,n$
154841
Computing symmetry/combinatorial factor for a diagram in $\phi^4$ theory
115258
Find all positive integers $n$ such that $\phi(n)+\sigma(n)=2n$.
157711
Number Theory: Prove that $m | \phi(a^m - 1)$
30601
Number of $60$th primitive roots of $-1$
117681
For which Natural $n\ge2: \phi(n)=n/2$
87289
Find the multiplicative inverses of all the elements in $\Bbb Z_{16}^\times$
136623
Hints/ Solution in finding a formula $\phi(n)$ for a binary square matrix
68385
Prove that $ \frac{n}{\phi(n)} = \sum\limits_{d \mid n} \frac{\mu^2(d)}{\phi(d)} $
123891
There are finitely many maps on nonnegative integers satisfying $\phi(ab)=\phi(a)+\phi(b)$
37012
The number of summands $\phi(n)$
15000
Show that number of elements in $(Z/nZ)^*$ is $\phi (n)$
53042
Find solutions to $\varphi\left(n\right)=2^{32}$
84491
Finding the smallest positive integer $n$ such that $S_n$ contains an element of order 60.
78342
When is $\phi(n)$ a prime number?
124333
A bijection between $\mathbb{N}$ and $\mathbb{P}(\mathbb{N})$?