18421997368 has 64 divisors (see below), whose sum is σ = 37461035520. Its totient is φ = 8460441600.

The previous prime is 18421997359. The next prime is 18421997387. The reversal of 18421997368 is 86379912481.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1370038 + ... + 1383418.

It is an arithmetic number, because the mean of its divisors is an integer number (585328680).

Almost surely, 2^18421997368 is an apocalyptic number.

It is an amenable number.

18421997368 is an abundant number, since it is smaller than the sum of its proper divisors (19039038152).

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

18421997368 is a wasteful number, since it uses less digits than its factorization.

18421997368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13648 (or 13644 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 58.

The spelling of 18421997368 in words is "eighteen billion, four hundred twenty-one million, nine hundred ninety-seven thousand, three hundred sixty-eight".