400 has 15 divisors: 1, 2, 4, 5, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200, 400.
15
400's divisors are 1, 2, 4, 5, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200, 400.
None of the positive common divisors of those numbers are multiples of 10.
The divisors of 800 are: 1, 2, 4, 5, 8, 10, 16, 20, 25, 32, 40, 50, 80, 100, 160, 200, 400, 800.
Divisors are used to divide numbers.
2,4,8 (1 and 16 are divisors too, but the number and 1 are always divisors)
The prime factors of 200 are 2 x 5 x 2 x 5 x 2. All possible multiples of those are all of 200's divisors. If you calculate all the divisors and add them up you will get the sum of divisors for 200. If that sum is greater than 400, then 200 is abundant. Here are a few examples of 200's divisors: 200, 100, 2, 50, 4, 8, 25. Already those add up to 391... if there are any more then 200 is certainly abundant. Does 200 have any other divisors?
136 has eight divisors.
The divisors of 41231 are: 1, 41231.
12 has six divisors.
The divisors of 61 are: 1, 61
320 has 14 divisors.