Divisor Sum of 523,776

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Example of Divisor Sum of Integer

$\map {\sigma_1} {523 \, 776} = 1 \, 571 \, 328$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$523 \, 776 = 2^9 \times 3 \times 11 \times 31$


Hence:

\(\ds \map {\sigma_1} {523 \, 776}\) \(=\) \(\ds \frac {2^{10} - 1} {2 - 1} \times \paren {3 + 1} \times \paren {11 + 1} \times \paren {31 + 1}\) Divisor Sum of Integer
\(\ds \) \(=\) \(\ds 1023 \times 4 \times 12 \times 32\)
\(\ds \) \(=\) \(\ds \paren {3 \times 11 \times 31} \times 2^2 \times \paren {2^2 \times 3} \times 2^5\)
\(\ds \) \(=\) \(\ds 2^9 \times 3^2 \times 11 \times 31\)
\(\ds \) \(=\) \(\ds 3 \times \paren {2^9 \times 3 \times 11 \times 31}\)
\(\ds \) \(=\) \(\ds 1 \, 571 \, 328\)

$\blacksquare$