18550537000 has 64 divisors (see below), whose sum is σ = 43896200400. Its totient is φ = 7336806400.

The previous prime is 18550536973. The next prime is 18550537013. The reversal of 18550537000 is 73505581.

It can be written as a sum of positive squares in 8 ways, for example, as 1991479876 + 16559057124 = 44626^2 + 128682^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15217 + ... + 193216.

Almost surely, 2^18550537000 is an apocalyptic number.

18550537000 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 18550537000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21948100200).

18550537000 is an abundant number, since it is smaller than the sum of its proper divisors (25345663400).

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

18550537000 is a wasteful number, since it uses less digits than its factorization.

18550537000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208543 (or 208529 counting only the distinct ones).

The product of its (nonzero) digits is 21000, while the sum is 34.

The spelling of 18550537000 in words is "eighteen billion, five hundred fifty million, five hundred thirty-seven thousand".