2059

Number
$2059$ (one thousand, nine hundred and eighteen) is:
 * $29 \times 71$


 * The $29$th heptagonal number after $1, 7, 18, 34, 55, 81, 112, \ldots, 874, 970, 1071, 1177, 1288, 1404, 1525, 1651, 1782, 1918$:
 * $2059 = \displaystyle \sum_{k \mathop = 1}^{29} \left({5 k - 4}\right) = \dfrac {29 \left({5 \times 29 - 3}\right)} 2$