560

Number
$560$ (five hundred and sixty) is:


 * $2^4 \times 5 \times 7$


 * The $14$th octagonal number, after $1$, $8$, $21$, $40$, $65$, $96$, $133$, $176$, $225$, $280$, $341$, $408$, $481$:
 * $560 = \displaystyle \sum_{k \mathop = 1}^{14} \left({6 k - 5}\right) = 14 \left({3 \times 14 - 2}\right)$


 * The $14$th tetrahedral number, after $1$, $4$, $10$, $20$, $35$, $56$, $84$, $120$, $165$, $220$, $286$, $364$, $455$:
 * $560 = \displaystyle \sum_{k \mathop = 1}^{14} \frac {k \left({k + 1}\right)} 2 = \dfrac {14 \left({14 + 1}\right) \left({14 + 2}\right)} 6$