4256

Number
$4256$ (four thousand, two hundred and fifty-six) is:


 * $2^5 \times 7 \times 19$


 * The $38$th octagonal number, after $1$, $8$, $21$, $40$, $65$, $\ldots$, $2296$, $2465$, $2640$, $2821$, $3008$, $3201$, $3400$, $3605$, $3816$, $4033$:
 * $4256 = \displaystyle \sum_{k \mathop = 1}^{38} \left({6 k - 5}\right) = 38 \left({3 \times 38 - 2}\right)$