18355639040 has 72 divisors (see below), whose sum is σ = 44139362400. Its totient is φ = 7313555456.

The previous prime is 18355639039. The next prime is 18355639051. The reversal of 18355639040 is 4093655381.

It is a junction number, because it is equal to n+sod(n) for n = 18355638982 and 18355639000.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 301061 + ... + 356859.

It is an arithmetic number, because the mean of its divisors is an integer number (613046700).

Almost surely, 2^18355639040 is an apocalyptic number.

18355639040 is a gapful number since it is divisible by the number (10) 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 18355639040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22069681200).

18355639040 is an abundant number, since it is smaller than the sum of its proper divisors (25783723360).

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

18355639040 is an equidigital number, since it uses as much as digits as its factorization.

18355639040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56077 (or 56063 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 44.

The spelling of 18355639040 in words is "eighteen billion, three hundred fifty-five million, six hundred thirty-nine thousand, forty".