Divisor Sum of 2024

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Example of Divisor Sum of Integer

$\map {\sigma_1} {2024} = 4320$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$2024 = 2^3 \times 11 \times 23$


Hence:

\(\ds \map {\sigma_1} {2024}\) \(=\) \(\ds \dfrac {2^4 - 1} {2 - 1} \times \paren {11 + 1} \times \paren {23 + 1}\) Divisor Sum of Integer
\(\ds \) \(=\) \(\ds 15 \times 12 \times 24\)
\(\ds \) \(=\) \(\ds \paren {3 \times 5} \times \paren {2^2 \times 3} \times \paren {2^3 \times 3}\)
\(\ds \) \(=\) \(\ds 2^5 \times 3^3 \times 5\)
\(\ds \) \(=\) \(\ds 4320\)

$\blacksquare$