at 3:40 sir has mentioned that we can also use the prime factorization to derive a formula for the sum of all divisors. What will be that formula?
How to calculate sum of all divisors
@Ishitagambhir refer this you will be able to get the formula then
https://www.math.upenn.edu/~deturck/m170/wk3/lecture/sumdiv.html#:~:text=In%20general%2C%20if%20you%20have,multiply%20all%20these%20sums%20together!
In general, if you have the prime factorization of the number n, then to calculate the sum of its divisors, you take each different prime factor and add together all its powers up to the one that appears in the prime factorization, and then multiply all these sums together!
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