9689

Number
$9689$ (nine thousand, six hundred and eighty-nine) is:


 * The $1196$th prime number


 * The index of the $21$st Mersenne prime after $2$, $3$, $5$, $7$, $13$, $17$, $19$, $31$, $61$, $89$, $107$, $127$, $521$, $607$, $1279$, $2203$, $2281$, $3217$, $4253$, $4423$:
 * $M_{9689} = 2^{9689} - 1 \approx 4 \cdotp 782 \times 10^{2916}$