276

Number
$276$ (two hundred and seventy-six) is:


 * $2^2 \times 3 \times 23$


 * The $23$nd triangular number after $1, 3, 6, 10, 15, \ldots, 136, 153, 171, 190, 210, 231, 253$:
 * $276 = \displaystyle \sum_{k \mathop = 1}^{23} k = \dfrac {23 \times \left({23 + 1}\right)} 2$


 * The $12$th hexagonal number after $1, 6, 15, 28, 45, 66, 91, 120, 153, 190, 231$:
 * $276 = \displaystyle \sum_{k \mathop = 1}^{12} \left({4 k - 3}\right) = 12 \left({2 \times 12 - 1}\right)$


 * The $19$th untouchable number after $2, 5, 52, 88, 96, 120, 124, 146, 162, 188, 206, 210, 216, 238, 246, 248, 262, 268$.


 * The $14$th inconsummate number after $62, 63, 65, 75, 84, 95, 161, 173, 195, 216, 261, 266, 272$:
 * $\nexists n \in \Z_{>0}: n = 276 \times s_{10} \left({n}\right)$


 * The smallest positive integer which begins an aliquot sequence whose final status is unknown.