18392721408 has 96 divisors (see below), whose sum is σ = 54483811200. Its totient is φ = 6130888704.

The previous prime is 18392721407. The next prime is 18392721437. The reversal of 18392721408 is 80412729381.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (18392721407) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111016 + ... + 221607.

It is an arithmetic number, because the mean of its divisors is an integer number (567539700).

Almost surely, 2^18392721408 is an apocalyptic number.

18392721408 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

18392721408 is an abundant number, since it is smaller than the sum of its proper divisors (36091089792).

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

18392721408 is an equidigital number, since it uses as much as digits as its factorization.

18392721408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332654 (or 332628 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The spelling of 18392721408 in words is "eighteen billion, three hundred ninety-two million, seven hundred twenty-one thousand, four hundred eight".