6,700,417

Number
$6 \, 700 \, 417$ is:


 * The $457 \, 523$rd prime number


 * One of the two prime factors of the $6$th Fermat number $2^{\paren {2^5} } + 1$, the other being $641$:
 * $6 \, 700 \, 417 = 52 \, 347 \times 2^7 + 1$