18243564938 has 16 divisors (see below), whose sum is σ = 27881907264. Its totient is φ = 8950656000.

The previous prime is 18243564931. The next prime is 18243565003. The reversal of 18243564938 is 83946534281.

It is a self number, because there is not a number n which added to its sum of digits gives 18243564938.

It is not an unprimeable number, because it can be changed into a prime (18243564931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 230438 + ... + 299313.

It is an arithmetic number, because the mean of its divisors is an integer number (1742619204).

Almost surely, 2^18243564938 is an apocalyptic number.

18243564938 is a deficient number, since it is larger than the sum of its proper divisors (9638342326).

18243564938 is a wasteful number, since it uses less digits than its factorization.

18243564938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 530077.

The product of its digits is 4976640, while the sum is 53.

The spelling of 18243564938 in words is "eighteen billion, two hundred forty-three million, five hundred sixty-four thousand, nine hundred thirty-eight".