Question

(15), ()=sum of all positive divisors of ,∈

Answer 1

Answer:

If the prime factorization of nn is

n=∏kpakk,n=∏kpkak,

where the pkpk are the distinct prime factors and the akak are the positive integer exponents, the sum of all the positive integer factors is

∏k(∑i=0akpik).∏k(∑i=0akpki).

For example, the sum of all of the factors of 120=23⋅3⋅5120=23⋅3⋅5 is

(1+2+22+23)(1+3)(1+5)=15⋅4⋅6=360.