18456993816 has 64 divisors (see below), whose sum is σ = 48269329920. Its totient is φ = 5870092800.

The previous prime is 18456993799. The next prime is 18456993847. The reversal of 18456993816 is 61839965481.

It is a self number, because there is not a number n which added to its sum of digits gives 18456993816.

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 15 ways as a sum of consecutive naturals, for example, 179661 + ... + 263043.

It is an arithmetic number, because the mean of its divisors is an integer number (754208280).

Almost surely, 2^18456993816 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 18456993816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24134664960).

18456993816 is an abundant number, since it is smaller than the sum of its proper divisors (29812336104).

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

18456993816 is a wasteful number, since it uses less digits than its factorization.

18456993816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83816 (or 83812 counting only the distinct ones).

The product of its digits is 11197440, while the sum is 60.

The spelling of 18456993816 in words is "eighteen billion, four hundred fifty-six million, nine hundred ninety-three thousand, eight hundred sixteen".