663

Number
$663$ (six hundred and sixty-three) is:
 * $2 \times 13 \times 17$


 * The $33$rd Smith number after $4$, $22$, $27$, $58$, $\ldots$, $576$, $588$, $627$, $634$, $636$, $645$, $648$, $654$:
 * $6 + 6 + 3 = 2 + 1 + 3 + 1 + 7 = 15$