18385890544 has 60 divisors (see below), whose sum is σ = 41471461728. Its totient is φ = 7873420800.

The previous prime is 18385890539. The next prime is 18385890613. The reversal of 18385890544 is 44509858381.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1058409 + ... + 1075639.

Almost surely, 2^18385890544 is an apocalyptic number.

18385890544 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18385890544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20735730864).

18385890544 is an abundant number, since it is smaller than the sum of its proper divisors (23085571184).

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

18385890544 is a wasteful number, since it uses less digits than its factorization.

18385890544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18614 (or 18601 counting only the distinct ones).

The product of its (nonzero) digits is 5529600, while the sum is 55.

The spelling of 18385890544 in words is "eighteen billion, three hundred eighty-five million, eight hundred ninety thousand, five hundred forty-four".