1288

Number
$1288$ (one thousand, two hundred and eighty-eight) is:
 * $2^3 \times 7 \times 23$


 * The $23$rd heptagonal number after $1, 7, 18, 34, 55, 81, 112, 148, 189, 235, 286, 342, 403, 469, 540, 616, 697, 783, 874, 970, 1071, 1177$:
 * $1288 = \displaystyle \sum_{k \mathop = 1}^{23} \left({5 k - 4}\right) = \dfrac {23 \left({5 \times 23 - 3}\right)} 2$