18978716544 has 32 divisors (see below), whose sum is σ = 50412216840. Its totient is φ = 6326238720.

The previous prime is 18978716539. The next prime is 18978716563. The reversal of 18978716544 is 44561787981.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24711487 + ... + 24712254.

Almost surely, 2^18978716544 is an apocalyptic number.

It is an amenable number.

18978716544 is an abundant number, since it is smaller than the sum of its proper divisors (31433500296).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18978716544 is an equidigital number, since it uses as much as digits as its factorization.

18978716544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49423758 (or 49423746 counting only the distinct ones).

The product of its digits is 13547520, while the sum is 60.

The spelling of 18978716544 in words is "eighteen billion, nine hundred seventy-eight million, seven hundred sixteen thousand, five hundred forty-four".