18317189820 has 48 divisors (see below), whose sum is σ = 51545894400. Its totient is φ = 4860035136.

The previous prime is 18317189789. The next prime is 18317189899. The reversal of 18317189820 is 2898171381.

It is a happy number.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 18317189820.

It is a congruent number.

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, 755112 + ... + 778991.

It is an arithmetic number, because the mean of its divisors is an integer number (1073872800).

Almost surely, 2^18317189820 is an apocalyptic number.

18317189820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18317189820 is an abundant number, since it is smaller than the sum of its proper divisors (33228704580).

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

18317189820 is a wasteful number, since it uses less digits than its factorization.

18317189820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1534314 (or 1534312 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 48.

The spelling of 18317189820 in words is "eighteen billion, three hundred seventeen million, one hundred eighty-nine thousand, eight hundred twenty".