18776136961 has 2 divisors, whose sum is σ = 18776136962. Its totient is φ = 18776136960.

The previous prime is 18776136949. The next prime is 18776136979. The reversal of 18776136961 is 16963167781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16390400625 + 2385736336 = 128025^2 + 48844^2 .

It is a cyclic number.

It is not a de Polignac number, because 18776136961 - 2⁷ = 18776136833 is a prime.

It is not a weakly prime, because it can be changed into another prime (18776139961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9388068480 + 9388068481.

It is an arithmetic number, because the mean of its divisors is an integer number (9388068481).

Almost surely, 2^18776136961 is an apocalyptic number.

It is an amenable number.

18776136961 is a deficient number, since it is larger than the sum of its proper divisors (1).

18776136961 is an equidigital number, since it uses as much as digits as its factorization.

18776136961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2286144, while the sum is 55.

The spelling of 18776136961 in words is "eighteen billion, seven hundred seventy-six million, one hundred thirty-six thousand, nine hundred sixty-one".