+862 A positive integer is called terrific if it has exactly $12$ positive divisors. A positive integer is called fine if it has exactly 2 positive divisors. Which numbers are fine?
+1279
A positive integer is called fine if it has exactly 2 positive divisors. Which numbers are fine?
I'll take a stab at it. I'll say the numbers that are the product of two prime numbers.
For the purpose of my submission, I exclude counting 1 and the number itself as divisors.
For example, 17 does not count as fine because 1 and 17 itself are disqualified as divisors.
However, 34 would count as fine because its divisors, i.e., 2 and 17, both are prime numbers.
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