18538521685204 has 12 divisors (see below), whose sum is σ = 32442444242964. Its totient is φ = 9269251901504.

The previous prime is 18538521685171. The next prime is 18538521685223. The reversal of 18538521685204 is 40258612583581.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 11491896600900 + 7046625084304 = 3389970^2 + 2654548^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5116632 + ... + 7953424.

It is an arithmetic number, because the mean of its divisors is an integer number (2703537020247).

Almost surely, 2^{18538521685204} is an apocalyptic number.

It is an amenable number.

18538521685204 is a deficient number, since it is larger than the sum of its proper divisors (13903922557760).

18538521685204 is a wasteful number, since it uses less digits than its factorization.

18538521685204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4470554 (or 4470552 counting only the distinct ones).

The product of its (nonzero) digits is 18432000, while the sum is 58.

The spelling of 18538521685204 in words is "eighteen trillion, five hundred thirty-eight billion, five hundred twenty-one million, six hundred eighty-five thousand, two hundred four".