18664881056 has 12 divisors (see below), whose sum is σ = 36746484642. Its totient is φ = 9332440512.

The previous prime is 18664881049. The next prime is 18664881083. The reversal of 18664881056 is 65018846681.

It can be written as a sum of positive squares in only one way, i.e., 18654096400 + 10784656 = 136580^2 + 3284^2 .

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 18664880989 and 18664881007.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 291638735 + ... + 291638798.

Almost surely, 2^18664881056 is an apocalyptic number.

18664881056 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

18664881056 is a deficient number, since it is larger than the sum of its proper divisors (18081603586).

18664881056 is an equidigital number, since it uses as much as digits as its factorization.

18664881056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 583277543 (or 583277535 counting only the distinct ones).

The product of its (nonzero) digits is 2211840, while the sum is 53.

The spelling of 18664881056 in words is "eighteen billion, six hundred sixty-four million, eight hundred eighty-one thousand, fifty-six".