Numbers such that Divisor Count divides Phi divides Divisor Sum/Examples/264

Examples of Numbers such that Divisor Count divides Phi divides Divisor Sum

The number $264$ has the property that:

$\map {\sigma_0} {264} \divides \map \phi {264} \divides \map {\sigma_1} {264}$

where:

$\divides$ denotes divisibility

$\sigma_0$ denotes the divisor count function

$\phi$ denotes the Euler $\phi$ (phi) function

$\sigma_1$ denotes the divisor sum function.

Proof

\(\ds \map {\sigma_0} {264}\)

\(=\)

\(\, \ds 16 \, \)

\(\ds \)

$\sigma_0$ of $264$

\(\ds \map \phi {264}\)

\(=\)

\(\, \ds 80 \, \)

\(\, \ds = \, \)

\(\ds 5 \times 16\)

$\phi$ of $264$

\(\ds \map {\sigma_1} {264}\)

\(=\)

\(\, \ds 720 \, \)

\(\, \ds = \, \)

\(\ds 9 \times 80\)

$\sigma_1$ of $264$

$\blacksquare$