3201

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Number

$3201$ (three thousand, two hundred and one) is:

$3 \times 11 \times 97$


The $33$rd octagonal number, after $1$, $8$, $21$, $40$, $65$, $\ldots$, $1281$, $1408$, $1541$, $1680$, $1825$, $1976$, $2133$, $2296$, $2465$, $2640$, $2821$, $3008$:
$3201 = \ds \sum_{k \mathop = 1}^{33} \paren {6 k - 5} = 33 \paren {3 \times 33 - 2}$


Also see