18185000000 has 112 divisors (see below), whose sum is σ = 45119611056. Its totient is φ = 7272000000.

The previous prime is 18184999969. The next prime is 18185000003. The reversal of 18185000000 is 58181.

It can be written as a sum of positive squares in 8 ways, for example, as 8696681536 + 9488318464 = 93256^2 + 97408^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 18185000000.

It is not an unprimeable number, because it can be changed into a prime (18185000003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4998182 + ... + 5001818.

Almost surely, 2^18185000000 is an apocalyptic number.

18185000000 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 18185000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22559805528).

18185000000 is an abundant number, since it is smaller than the sum of its proper divisors (26934611056).

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

18185000000 is an frugal number, since it uses more digits than its factorization.

18185000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3684 (or 3644 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 23.

Adding to 18185000000 its reverse (58181), we get a palindrome (18185058181).

The spelling of 18185000000 in words is "eighteen billion, one hundred eighty-five million", and thus it is an aban number.