2300

Number
$2300$ (two thousand three hundred) is:
 * $2^2 \times 5^2 \times 23$


 * The $23$rd tetrahedral number, after $1$, $4$, $10$, $20$, $35$, $\ldots$, $816$, $969$, $1140$, $1330$, $1540$, $1771$, $2024$:
 * $2300 = \ds \sum_{k \mathop = 1}^{23} \frac {k \paren {k + 1} } 2 = \dfrac {23 \paren {23 + 1} \paren {23 + 2} } 6$