2176

Number
$2176$ (two thousand, one hundred and seventy-six) is:


 * $2^7 \times 17$


 * The $16$th pentagonal pyramidal number after $1$, $6$, $12$, $40$, $75$, $126$, $196$, $288$, $405$, $550$, $726$, $936$, $1183$, $1470$, $1800$:
 * $2176 = \displaystyle \sum_{k \mathop = 1}^{16} \dfrac {k \left({3 k - 1}\right)} 2 = \dfrac {16^2 \left({16 + 1}\right)} 2$