2185
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Number
$2185$ (two thousand, one hundred and eighty-five) is:
- $5 \times 19 \times 23$
- The $2$nd term of a sequence of $17$ consecutive integers all of which are not coprime with the product of the other $16$:
- $2185 \not \perp \ds \prod_{\substack {2184 \mathop \le k \mathop \le 2200 \\ k \mathop \ne 2185} } k$
- The $38$th second pentagonal number after $2$, $7$, $15$, $26$, $\ldots$, $1107$, $1190$, $1276$, $1365$, $1457$, $1552$, $1650$, $1751$, $1855$, $1962$, $2072$:
- $2185 = \dfrac {38 \paren {3 \times 38 + 1} } 2$
- The $76$th generalized pentagonal number after $1$, $2$, $5$, $7$, $12$, $15$, $\ldots$, $1617$, $1650$, $1717$, $1751$, $1820$, $1855$, $1926$, $1962$, $2072$, $2147$:
- $2185 = \dfrac {38 \paren {3 \times 38 + 1} } 2$