10,206

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Number

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

$2 \times 3^6 \times 7$


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


Also see