18656438018 has 8 divisors (see below), whose sum is σ = 28036386300. Its totient is φ = 9310975920.

The previous prime is 18656437981. The next prime is 18656438039. The reversal of 18656438018 is 81083465681.

It can be written as a sum of positive squares in 2 ways, for example, as 18635799169 + 20638849 = 136513^2 + 4543^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8620193 + ... + 8622356.

Almost surely, 2^18656438018 is an apocalyptic number.

18656438018 is a deficient number, since it is larger than the sum of its proper divisors (9379948282).

18656438018 is a wasteful number, since it uses less digits than its factorization.

18656438018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17243092.

The product of its (nonzero) digits is 1105920, while the sum is 50.

The spelling of 18656438018 in words is "eighteen billion, six hundred fifty-six million, four hundred thirty-eight thousand, eighteen".