2600

Number
$2600$ (two thousand six hundred) is:
 * $2^3 \times 5^2 \times 13$


 * The $24$th tetrahedral number, after $1$, $4$, $10$, $20$, $35$, $\ldots$, $816$, $969$, $1140$, $1330$, $1540$, $1771$, $2024$, $2300$:
 * $2600 = \displaystyle \sum_{k \mathop = 1}^{24} \frac {k \left({k + 1}\right)} 2 = \dfrac {24 \left({24 + 1}\right) \left({24 + 2}\right)} 6$