18431212777 has 2 divisors, whose sum is σ = 18431212778. Its totient is φ = 18431212776.

The previous prime is 18431212763. The next prime is 18431212801. The reversal of 18431212777 is 77721213481.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9750377536 + 8680835241 = 98744^2 + 93171^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18431212777 is a prime.

It is not a weakly prime, because it can be changed into another prime (18431212757) 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, 9215606388 + 9215606389.

It is an arithmetic number, because the mean of its divisors is an integer number (9215606389).

Almost surely, 2^18431212777 is an apocalyptic number.

It is an amenable number.

18431212777 is a deficient number, since it is larger than the sum of its proper divisors (1).

18431212777 is an equidigital number, since it uses as much as digits as its factorization.

18431212777 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 131712, while the sum is 43.

The spelling of 18431212777 in words is "eighteen billion, four hundred thirty-one million, two hundred twelve thousand, seven hundred seventy-seven".