1015

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Number

$1015$ (one thousand, one hundred and fifteen) is:

$5 \times 7 \times 29$


The $14$th square pyramidal number after $1$, $5$, $14$, $30$, $55$, $91$, $140$, $204$, $285$, $385$, $506$, $650$, $819$:
$1015 = \ds \sum_{k \mathop = 1}^{14} k^2 = \dfrac {14 \paren {14 + 1} \paren {2 \times 14 + 1} } 6$


Also see