Divisor Sum of 83,328

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Example of Divisor Sum of Integer

$\map {\sigma_1} {83 \, 328} = 261 \, 120$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$83 \, 328 = 2^7 \times 3 \times 7 \times 31$

Hence:

\(\ds \map {\sigma_1} {83 \, 328}\) \(=\) \(\ds \frac {2^8 - 1} {2 - 1} \times \paren {3 + 1} \times \paren {7 + 1} \times \paren {31 + 1}\) Divisor Sum of Integer
\(\ds \) \(=\) \(\ds 255 \times 4 \times 8 \times 32\)
\(\ds \) \(=\) \(\ds \paren {3 \times 5 \times 17} \times 2^2 \times 2^3 \times 2^5\)
\(\ds \) \(=\) \(\ds 2^{10} \times 3 \times 5 \times 17\)
\(\ds \) \(=\) \(\ds 261 \, 120\)

$\blacksquare$