4347

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Number

$4347$ (four thousand, three hundred and forty-seven) is:

$3^3 \times 7 \times 23$


The $42$nd heptagonal number after $1$, $7$, $18$, $34$, $55$, $81$, $112$, $\ldots$, $3010$, $3186$, $3367$, $3744$, $3940$, $4141$:
$4347 = \ds \sum_{k \mathop = 1}^{42} \paren {5 k - 4} = \dfrac {42 \paren {5 \times 42 - 3} } 2$


Also see