63

Number
$63$ (sixty-three) is:


 * $3^2 \times 7$


 * The $4$th Woodall number after $1, 7, 23$:
 * $63 = 4 \times 2^4 - 1$


 * The $15$th lucky number:
 * $1, 3, 7, 9, 13, 15, 21, 25, 31, 33, 37, 43, 49, 51, 63, \ldots$


 * The $3$rd of the $1$st ordered quadruple of consecutive integers that have sigma values which are strictly increasing:
 * $\sigma \left({61}\right) = 62$, $\sigma \left({62}\right) = 96$, $\sigma \left({63}\right) = 104$, $\sigma \left({64}\right) = 127$


 * The $2$nd inconsummate number after $62$:
 * $\nexists n \in \Z_{>0}: n = 63 \times s_{10} \left({n}\right)$