Prime squares, such as 4, 9, 25, 49 and 121.
There are three of them with exactly five factors.
There are no prime numbers with three factors. By definition, a prime number has exactly two factors - 1 and itself.
Any three-digit multiple of 60, from 120 to 960, has the first five counting numbers as factors.
625
2081 has two factors, one of them is prime. 72570 has thirty-two factors, five of them are prime. 50 has six factors, three of them are prime.
There are five numbers in that range with 12 factors, but none with exactly eleven.
105, 210, 315
30 and 60
There are five of them: 31 37 41 43 47
4, 9, 25, 49, 121
60, 120, 180.....
720.