18319820500 has 48 divisors (see below), whose sum is σ = 42364065744. Its totient is φ = 6896870400.

The previous prime is 18319820447. The next prime is 18319820509. The reversal of 18319820500 is 502891381.

It can be written as a sum of positive squares in 8 ways, for example, as 5635204624 + 12684615876 = 75068^2 + 112626^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 18319820500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18319820509) 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, 1069137 + ... + 1086136.

It is an arithmetic number, because the mean of its divisors is an integer number (882584703).

Almost surely, 2^18319820500 is an apocalyptic number.

18319820500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18319820500 is an abundant number, since it is smaller than the sum of its proper divisors (24044245244).

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

18319820500 is a wasteful number, since it uses less digits than its factorization.

18319820500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2155309 (or 2155297 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 37.

The spelling of 18319820500 in words is "eighteen billion, three hundred nineteen million, eight hundred twenty thousand, five hundred".