Find all positive integers $n$ that have precisely $\sqrt{n + 1}$ natural divisors.
Problem
Source: 2022 Saudi Arabia January Camp Test 2.2 BMO + EGMO TST
Tags: number theory, Divisors
Source: 2022 Saudi Arabia January Camp Test 2.2 BMO + EGMO TST
Tags: number theory, Divisors
Find all positive integers $n$ that have precisely $\sqrt{n + 1}$ natural divisors.