68

Number
$68$ (sixty-eight) is:
 * $2^2 \times 17$


 * The $7$th nontotient after $14, 26, 34, 38, 50, 62$:
 * $\nexists m \in \Z_{>0}: \phi \left({m}\right) = 68$
 * where $\phi \left({m}\right)$ denotes the Euler $\phi$ function