Finding sum of factors of a number using prime factorization Given a number, there is an algorithm described here to find it's sum and number of factors.
For example, let us take the number $1225$ :
It's factors are $1, 5, 7, 25, 35, 49, 175, 245, 1225 $
and the sum of factors are $1767$.
A simple algorithm that is described to find the sum of the factors is using prime factorization.
$1225 = 5^2 \cdot 7^2$, therefore the sum of factors is $ (1+5+25)(1+7+49)  = 1767$
But this logic does not work for the number $2450$. Please check if it's working for $2450$
Edit :
Sorry it works for $2450$. I made some mistake in calculation.

Solving for $1225 = 5^2 × 7^2$
Sum of divisors = $(a^{p+1}  – 1)/(a – 1) × (b^{q+1}  – 1)/(b – 1)$
Here $a = 5$, $b = 7$ prime factors
$p = 2$ and $q = 2$
Sum of divisors  = $(5^3 – 1)/(5 – 1) ×  (7^3 – 1)/(7 – 1)$
= $(124/4) ×  (342/6)$
= $(31 × 57)$
= $1767$
