10,206

Number
$10 \, 206$ (ten thousand, two hundred and six) is:


 * $2 \times 3^6 \times 7$


 * The $27$th pentagonal pyramidal number after $1, 6, 12, 40, 75, \ldots, 1470, 1800, 2176, 2601, 3078, 3610, 4200, 4851, 5566, 6348, 7200, 8125, 9126$:
 * $10 \, 206 = \displaystyle \sum_{k \mathop = 1}^{27} \dfrac {k \left({3 k - 1}\right)} 2 = \dfrac {27^2 \left({27 + 1}\right)} 2$