Divisor Sum of 17,325

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Example of Divisor Sum of Integer

$\map {\sigma_1} {17 \, 325} = 38 \, 688$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$17 \, 325 = 3^2 \times 5^2 \times 7 \times 11$


Hence:

\(\ds \map {\sigma_1} {17 \, 325}\) \(=\) \(\ds \dfrac {3^3 - 1} {3 - 1} \times \dfrac {5^3 - 1} {5 - 1} \times \paren {7 + 1} \times \paren {11 + 1}\) Divisor Sum of Integer
\(\ds \) \(=\) \(\ds \dfrac {26} 2 \times \dfrac {124} 4 \times 8 \times 12\)
\(\ds \) \(=\) \(\ds 13 \times 31 \times 8 \times 12\)
\(\ds \) \(=\) \(\ds 13 \times 31 \times 2^3 \times \paren {2^2 \times 3}\)
\(\ds \) \(=\) \(\ds 2^5 \times 3 \times 13 \times 31\)
\(\ds \) \(=\) \(\ds 38 \, 688\)

$\blacksquare$