Problem 694

Erdős Problem #694: declared status 'solved'. Formalized: yes. Let $f_{\max}(n)$ be the largest $m$ such that $\phi(m)=n$, and $f_{\min}(n)$ be the smallest such $m$, where $\phi$ is Euler's totient function. Investigate$$\max_{n\leq x}\frac{f_{\max}(n)}{f_{\min}(n)}.$$ Prize: no. Tags: number theory.