18939834368 has 416 divisors, whose sum is σ = 51190473600. Its totient is φ = 6936330240.

The previous prime is 18939834349. The next prime is 18939834371. The reversal of 18939834368 is 86343893981.

It is a tau number, because it is divible by the number of its divisors (416).

It is a self number, because there is not a number n which added to its sum of digits gives 18939834368.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 310489058 + ... + 310489118.

Almost surely, 2^18939834368 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18939834368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25595236800).

18939834368 is an abundant number, since it is smaller than the sum of its proper divisors (32250639232).

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

18939834368 is an equidigital number, since it uses as much as digits as its factorization.

18939834368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136 (or 100 counting only the distinct ones).

The product of its digits is 26873856, while the sum is 62.

The spelling of 18939834368 in words is "eighteen billion, nine hundred thirty-nine million, eight hundred thirty-four thousand, three hundred sixty-eight".