18685500500 has 24 divisors (see below), whose sum is σ = 40809134184. Its totient is φ = 7474200000.

The previous prime is 18685500497. The next prime is 18685500503. The reversal of 18685500500 is 500558681.

It is an interprime number because it is at equal distance from previous prime (18685500497) and next prime (18685500503).

It can be written as a sum of positive squares in 4 ways, for example, as 4008662596 + 14676837904 = 63314^2 + 121148^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18685500503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18685001 + ... + 18686000.

It is an arithmetic number, because the mean of its divisors is an integer number (1700380591).

Almost surely, 2^18685500500 is an apocalyptic number.

18685500500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18685500500 is an abundant number, since it is smaller than the sum of its proper divisors (22123633684).

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

18685500500 is a wasteful number, since it uses less digits than its factorization.

18685500500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37371020 (or 37371008 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 38.

The spelling of 18685500500 in words is "eighteen billion, six hundred eighty-five million, five hundred thousand, five hundred".