18044405640 has 320 divisors, whose sum is σ = 64282363200. Its totient is φ = 4527124992.

The previous prime is 18044405627. The next prime is 18044405677. The reversal of 18044405640 is 4650444081.

It is a happy number.

18044405640 is a `hidden beast` number, since 1 + 8 + 0 + 4 + 4 + 4 + 0 + 5 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 18044405595 and 18044405604.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 9663987 + ... + 9665853.

It is an arithmetic number, because the mean of its divisors is an integer number (200882385).

Almost surely, 2^18044405640 is an apocalyptic number.

18044405640 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 18044405640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32141181600).

18044405640 is an abundant number, since it is smaller than the sum of its proper divisors (46237957560).

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

18044405640 is a wasteful number, since it uses less digits than its factorization.

18044405640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2066 (or 2053 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 36.

The spelling of 18044405640 in words is "eighteen billion, forty-four million, four hundred five thousand, six hundred forty".