MathNet 2023-part-06 — 191 problems (EN–VI) Question 29

A divisor of a positive integer $n$ is a proper divisor if it is different from 1 and $n$. For how many positive integers $n$ is the number 17 the largest proper divisor?

(A) 0
(B) 1
(C) 3
(D) 5
(E) 7