18779995837 has 2 divisors, whose sum is σ = 18779995838. Its totient is φ = 18779995836.

The previous prime is 18779995799. The next prime is 18779995847. The reversal of 18779995837 is 73859997781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10451790756 + 8328205081 = 102234^2 + 91259^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18779995837 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18779995837.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18779995847) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9389997918 + 9389997919.

It is an arithmetic number, because the mean of its divisors is an integer number (9389997919).

Almost surely, 2^18779995837 is an apocalyptic number.

It is an amenable number.

18779995837 is a deficient number, since it is larger than the sum of its proper divisors (1).

18779995837 is an equidigital number, since it uses as much as digits as its factorization.

18779995837 is an evil number, because the sum of its binary digits is even.

The product of its digits is 240045120, while the sum is 73.

The spelling of 18779995837 in words is "eighteen billion, seven hundred seventy-nine million, nine hundred ninety-five thousand, eight hundred thirty-seven".