1128

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Number

$1128$ (one thousand, one hundred and twenty-eight) is:

$2^3 \times 3 \times 47$


The $24$th hexagonal number after $1$, $6$, $15$, $28$, $45$, $66$, $91$, $\ldots$, $703$, $780$, $861$, $946$, $1035$:
$1128 = \ds \sum_{k \mathop = 1}^{24} \paren {4 k - 3} = 24 \paren {2 \times 24 - 1}$


The $47$th triangular number after $1$, $3$, $6$, $10$, $15$, $\ldots$, $496$, $528$, $561$, $595$, $630$, $666$, $703$, $741$, $780$, $820$, $861$, $903$, $946$, $990$, $1035$, $1081$:
$1128 = \ds \sum_{k \mathop = 1}^{47} k = \dfrac {47 \times \paren {47 + 1} } 2$


Also see