618,970,019,642,690,137,449,562,111/Historical Note

Historical Note on $618 \, 970,019 \, 642 \, 690 \, 137 \, 449 \, 562 \, 111$
$618 \, 970,019 \, 642 \, 690 \, 137 \, 449 \, 562 \, 111 = 2^{89} - 1$ was discovered to be prime in $1911$ by.

It was the $11$th Mersenne prime to be discovered, although the $10$th in sequence.

had demonstrated in $1876$ that $2^{127} - 1$ (actually the $12$th in sequence) is prime.