106

Number
$106$ (one hundred and six) is:


 * $2 \times 53$


 * The $34$th semiprime:
 * $106 = 2 \times 53$


 * The $2$nd of the $1$st ordered triple of consecutive integers that have Euler $\phi$ values which are strictly increasing:
 * $\phi \left({105}\right) = 48$, $\phi \left({106}\right) = 52$, $\phi \left({107}\right) = 106$


 * The $3$rd of the $2$nd ordered quadruple of consecutive integers that have sigma values which are strictly decreasing:
 * $\sigma \left({104}\right) = 210, \ \sigma \left({105}\right) = 192, \ \sigma \left({106}\right) = 162, \ \sigma \left({107}\right) = 108$

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