Divisor Sum of 177,792

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Example of Divisor Sum of Integer

$\map {\sigma_1} {177 \, 792} = 473 \, 280$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$177 \, 792 = 2^7 \times 3 \times 7 \times 463$


Hence:

\(\ds \map {\sigma_1} {177 \, 792}\) \(=\) \(\ds \frac {2^8 - 1} {2 - 1} \times \paren {3 + 1} \times \paren {7 + 1} \times \paren {463 + 1}\) Divisor Sum of Integer
\(\ds \) \(=\) \(\ds 255 \times 4 \times 8 \times 464\)
\(\ds \) \(=\) \(\ds \paren {3 \times 5 \times 17} \times 2^2 \times 2^3 \times \paren {2^4 \times 29}\)
\(\ds \) \(=\) \(\ds 2^6 \times 3 \times 5 \times 17 \times 29\)
\(\ds \) \(=\) \(\ds 473 \, 280\)

$\blacksquare$