Divisor Sum of 2835

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Example of Divisor Sum of Integer

$\map {\sigma_1} {2835} = 5808$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$2835 = 3^4 \times 5 \times 7$


Hence:

\(\ds \map {\sigma_1} {2835}\) \(=\) \(\ds \dfrac {3^5 - 1} {3 - 1} \times \paren {5 + 1} \times \paren {7 + 1}\) Divisor Sum of Integer
\(\ds \) \(=\) \(\ds \dfrac {242} 2 \times 6 \times 8\)
\(\ds \) \(=\) \(\ds 121 \times 6 \times 8\)
\(\ds \) \(=\) \(\ds 11^2 \times \paren {2 \times 3} \times 2^3\)
\(\ds \) \(=\) \(\ds 2^4 \times 3 \times 11^2\)
\(\ds \) \(=\) \(\ds 5808\)

$\blacksquare$