18778868837 has 2 divisors, whose sum is σ = 18778868838. Its totient is φ = 18778868836.

The previous prime is 18778868833. The next prime is 18778868869. The reversal of 18778868837 is 73886887781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16310865796 + 2468003041 = 127714^2 + 49679^2 .

It is a cyclic number.

It is not a de Polignac number, because 18778868837 - 2² = 18778868833 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18778868833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9389434418 + 9389434419.

It is an arithmetic number, because the mean of its divisors is an integer number (9389434419).

Almost surely, 2^18778868837 is an apocalyptic number.

It is an amenable number.

18778868837 is a deficient number, since it is larger than the sum of its proper divisors (1).

18778868837 is an equidigital number, since it uses as much as digits as its factorization.

18778868837 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 202309632, while the sum is 71.

The spelling of 18778868837 in words is "eighteen billion, seven hundred seventy-eight million, eight hundred sixty-eight thousand, eight hundred thirty-seven".