The prime factors of 2015 are:
5 x 13 x 31
We can choose to include or exclude each of these prime factors and that will form 2 x 2 x 2 = 8 factors, namely:
1, 5, 13, 31, 65, 155, 403, 2015
We want to form another number that has exactly 8 factors. So we need 3 primes with one that overlaps with 2015. The obvious choice is 2 x 3 x 5
Answer:
30 is the smallest positive number that also has 8 divisors (namely, 1, 2, 3, 5, 6, 10, 15, 30)
