New posts in Totient Function

How can we prove that there are no other integers with $\phi(n)=2$ besides 3,4,6?

Calculating $\phi(100)$ where $\phi$ is the totient function

Find all positive integers $n$ such that $\varphi(n)$ divides $n^2 + 3$

Phi Function Summation and Divisors

Solutions to $\varphi(\varphi(a))=\varphi(\varphi(b))$

Why Euler's Totient function is important?

Evaluating $\sum_{n=1}^{\infty} \frac{\phi(n)}{7^n + 1}$, where $\phi(n)$ is Euler's totient function

Can a composite number $n$ be the arithmetic mean of $\sigma(n)$ and $\varphi(n)$?

Can I check, whether $n$ with $\frac{n}{\phi(n)}=r$ exists?

Only finitely many $n$ such that $\phi(n) = m$