18512185185 has 48 divisors (see below), whose sum is σ = 34645338000. Its totient is φ = 9090150912.

The previous prime is 18512185183. The next prime is 18512185187. The reversal of 18512185185 is 58158121581.

18512185185 is a `hidden beast` number, since 1 + 8 + 5 + 121 + 8 + 518 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (18512185183) and next prime (18512185187).

It can be written as a sum of positive squares in 8 ways, for example, as 8708809041 + 9803376144 = 93321^2 + 99012^2 .

It is not a de Polignac number, because 18512185185 - 2¹ = 18512185183 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 18512185185.

It is not an unprimeable number, because it can be changed into a prime (18512185183) 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 47 ways as a sum of consecutive naturals, for example, 186891 + ... + 268239.

It is an arithmetic number, because the mean of its divisors is an integer number (721777875).

Almost surely, 2^18512185185 is an apocalyptic number.

18512185185 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18512185185 is a deficient number, since it is larger than the sum of its proper divisors (16133152815).

18512185185 is a wasteful number, since it uses less digits than its factorization.

18512185185 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81762 (or 81759 counting only the distinct ones).

The product of its digits is 128000, while the sum is 45.

The spelling of 18512185185 in words is "eighteen billion, five hundred twelve million, one hundred eighty-five thousand, one hundred eighty-five".