Squares of Primes

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If we let $f(n)$ denote the sum of all the divisors of the integer $n$, how many integers $i$ exist such that $1 \le i \le 2010$ and $f(i) = 1 + \sqrt{i} + i$?

How do I find the solution to this problem? Here are my thoughts.

Thought Process 1: Find all perfect squares (of primes) less than 2010. Would that be correct?

I think that the answer is 14 ?