18813638113 has 4 divisors (see below), whose sum is σ = 18826805140. Its totient is φ = 18800471088.

The previous prime is 18813638111. The next prime is 18813638203. The reversal of 18813638113 is 31183631881.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1587863104 + 17225775009 = 39848^2 + 131247^2 .

It is a cyclic number.

It is not a de Polignac number, because 18813638113 - 2¹ = 18813638111 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18813638113.

It is not an unprimeable number, because it can be changed into a prime (18813638111) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6581370 + ... + 6584227.

It is an arithmetic number, because the mean of its divisors is an integer number (4706701285).

Almost surely, 2^18813638113 is an apocalyptic number.

It is an amenable number.

18813638113 is a deficient number, since it is larger than the sum of its proper divisors (13167027).

18813638113 is a wasteful number, since it uses less digits than its factorization.

18813638113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13167026.

The product of its digits is 82944, while the sum is 43.

The spelling of 18813638113 in words is "eighteen billion, eight hundred thirteen million, six hundred thirty-eight thousand, one hundred thirteen".