4921

Number
$4921$ (four thousand, nine hundred and twenty-one) is:


 * $7 \times 19 \times 37$


 * The $41$st centered hexagonal number after $1$, $7$, $19$, $37$, $61$, $91$, $127$, $\ldots$, $2791$, $2977$, $3169$, $3367$, $3571$, $3781$, $3997$, $4219$, $4447$, $4681$:
 * $4921 = \ds 1 + \sum_{k \mathop = 1}^{41 - 1} 6 k = 41^3 - 40^3$