Question

Problem 2 Find all the divisors of the number 2,310. How do you know that you found them all?​

Answer 1

9514 1404 393

Answer:

  1, 2, 3, 5, 6, 7, 10, 11, 14, 15, 21, 22, 30, 33, 35, 42,

  55, 66, 70, 77, 105, 110, 154, 165, 210, 231, 330, 385, 462, 770, 1155, 2310

Step-by-step explanation:

The trailing digit is 0, and the sum of digits is 6, so we know the number is divisible by 2, 3, 5. Dividing out those factors, we get a quotient of 77, which is 7×11. This means the prime factorization is ...

  2×3×5×7×11 = 2310

There are 5 prime factors, each with an exponent of 1, so the total number of divisors is 2^5 = 32. We will have found them all when all 32 are listed.

  1, 2, 3, 5, 6, 7, 10, 11, 14, 15, 21, 22, 30, 33, 35, 42,

  55, 66, 70, 77, 105, 110, 154, 165, 210, 231, 330, 385, 462, 770, 1155, 2310

Of course, the pairwise products working toward the center from the ends of the list are all 2310.