1404

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Number

$1404$ (one thousand, four hundred and four) is:

$2^2 \times 3^3 \times 13$


The $24$th heptagonal number after $1$, $7$, $18$, $34$, $55$, $81$, $112$, $\ldots$, $874$, $970$, $1071$, $1177$, $1288$:
$1404 = \ds \sum_{k \mathop = 1}^{24} \paren {5 k - 4} = \dfrac {24 \paren {5 \times 24 - 3} } 2$


Also see