Question

The positive integer k has exactly two positive prime factors, 3 and 7. if k has a total of 6 positive factors, including 1 and k, what is the value of k ?

Answer 1

I think there are two solutions, 63 or 147:

63 = 3² x 7, factors 1 | 3 | 7 | 9 | 21 | 63
147 = 3 x 7², factors 1 | 3 | 7 | 21 | 49 | 147