18311279968837 has 2 divisors, whose sum is σ = 18311279968838. Its totient is φ = 18311279968836.

The previous prime is 18311279968799. The next prime is 18311279968873. The reversal of 18311279968837 is 73886997211381.

Together with next prime (18311279968873) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13631092904961 + 4680187063876 = 3692031^2 + 2163374^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18311279968837 is a prime.

It is a super-2 number, since 2×18311279968837² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18311279968837.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18311279938837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9155639984418 + 9155639984419.

It is an arithmetic number, because the mean of its divisors is an integer number (9155639984419).

Almost surely, 2^{18311279968837} is an apocalyptic number.

It is an amenable number.

18311279968837 is a deficient number, since it is larger than the sum of its proper divisors (1).

18311279968837 is an equidigital number, since it uses as much as digits as its factorization.

18311279968837 is an evil number, because the sum of its binary digits is even.

The product of its digits is 219469824, while the sum is 73.

The spelling of 18311279968837 in words is "eighteen trillion, three hundred eleven billion, two hundred seventy-nine million, nine hundred sixty-eight thousand, eight hundred thirty-seven".