18878438839 has 4 divisors (see below), whose sum is σ = 20330626456. Its totient is φ = 17426251224.

The previous prime is 18878438837. The next prime is 18878438863. The reversal of 18878438839 is 93883487881.

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

It is a cyclic number.

It is not a de Polignac number, because 18878438839 - 2¹ = 18878438837 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18878438837) 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, 726093789 + ... + 726093814.

It is an arithmetic number, because the mean of its divisors is an integer number (5082656614).

Almost surely, 2^18878438839 is an apocalyptic number.

18878438839 is a deficient number, since it is larger than the sum of its proper divisors (1452187617).

18878438839 is a wasteful number, since it uses less digits than its factorization.

18878438839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1452187616.

The product of its digits is 74317824, while the sum is 67.

The spelling of 18878438839 in words is "eighteen billion, eight hundred seventy-eight million, four hundred thirty-eight thousand, eight hundred thirty-nine".