Divisor Sum of 17,716

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Example of Divisor Sum of Integer

$\map {\sigma_1} {17 \, 716} = 32 \, 032$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$17 \, 716 = 2^2 \times 43 \times 103$

Hence:

\(\ds \map {\sigma_1} {17 \, 716}\) \(=\) \(\ds \frac {2^3 - 1} {2 - 1} \times \paren {43 + 1} \times \paren {103 + 1}\) Divisor Sum of Integer
\(\ds \) \(=\) \(\ds 7 \times 44 \times 104\)
\(\ds \) \(=\) \(\ds 7 \times \paren {2^2 \times 11} \times \paren {2^3 \times 13}\)
\(\ds \) \(=\) \(\ds 2^5 \times 7 \times 11 \times 13\)
\(\ds \) \(=\) \(\ds 32 \, 032\)

$\blacksquare$