8138927939 has 4 divisors (see below), whose sum is σ = 8617688424. Its totient is φ = 7660167456.

The previous prime is 8138927903. The next prime is 8138927941. The reversal of 8138927939 is 9397298318.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8138927939 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8138927239) 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, 239380217 + ... + 239380250.

It is an arithmetic number, because the mean of its divisors is an integer number (2154422106).

Almost surely, 2^8138927939 is an apocalyptic number.

8138927939 is a deficient number, since it is larger than the sum of its proper divisors (478760485).

8138927939 is a wasteful number, since it uses less digits than its factorization.

8138927939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 478760484.

The product of its digits is 5878656, while the sum is 59.

The square root of 8138927939 is about 90216.0071107118. The cubic root of 8138927939 is about 2011.5109501612.

The spelling of 8138927939 in words is "eight billion, one hundred thirty-eight million, nine hundred twenty-seven thousand, nine hundred thirty-nine".