524,287

Number
$524 \, 287$ (five hundred and twenty-four thousand, two hundred and eighty-seven) is:


 * The $43 \, 390$th prime number


 * The $7$th Mersenne prime after $3$, $7$, $31$, $127$, $8191$, $131 \, 071$:
 * $524 \, 287 = 2^{19} - 1$