18438999552 has 120 divisors (see below), whose sum is σ = 53744450760. Its totient is φ = 6085324800.

The previous prime is 18438999529. The next prime is 18438999569. The reversal of 18438999552 is 25599983481.

It is a self number, because there is not a number n which added to its sum of digits gives 18438999552.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 445599 + ... + 485217.

It is an arithmetic number, because the mean of its divisors is an integer number (447870423).

Almost surely, 2^18438999552 is an apocalyptic number.

18438999552 is a gapful number since it is divisible by the number (12) 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 18438999552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26872225380).

18438999552 is an abundant number, since it is smaller than the sum of its proper divisors (35305451208).

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

18438999552 is a wasteful number, since it uses less digits than its factorization.

18438999552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39744 (or 39725 counting only the distinct ones).

The product of its digits is 27993600, while the sum is 63.

The spelling of 18438999552 in words is "eighteen billion, four hundred thirty-eight million, nine hundred ninety-nine thousand, five hundred fifty-two".