684279891137 has 2 divisors, whose sum is σ = 684279891138. Its totient is φ = 684279891136.

The previous prime is 684279891037. The next prime is 684279891149. The reversal of 684279891137 is 731198972486.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 621651825601 + 62628065536 = 788449^2 + 250256^2 .

It is a cyclic number.

It is not a de Polignac number, because 684279891137 - 2¹² = 684279887041 is a prime.

It is not a weakly prime, because it can be changed into another prime (684279891157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342139945568 + 342139945569.

It is an arithmetic number, because the mean of its divisors is an integer number (342139945569).

Almost surely, 2^684279891137 is an apocalyptic number.

It is an amenable number.

684279891137 is a deficient number, since it is larger than the sum of its proper divisors (1).

684279891137 is an equidigital number, since it uses as much as digits as its factorization.

684279891137 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36578304, while the sum is 65.

The spelling of 684279891137 in words is "six hundred eighty-four billion, two hundred seventy-nine million, eight hundred ninety-one thousand, one hundred thirty-seven".