128361918791 has 2 divisors, whose sum is σ = 128361918792. Its totient is φ = 128361918790.

The previous prime is 128361918781. The next prime is 128361918803. The reversal of 128361918791 is 197819163821.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128361918791 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128361918731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64180959395 + 64180959396.

It is an arithmetic number, because the mean of its divisors is an integer number (64180959396).

Almost surely, 2^128361918791 is an apocalyptic number.

128361918791 is a deficient number, since it is larger than the sum of its proper divisors (1).

128361918791 is an equidigital number, since it uses as much as digits as its factorization.

128361918791 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1306368, while the sum is 56.

The spelling of 128361918791 in words is "one hundred twenty-eight billion, three hundred sixty-one million, nine hundred eighteen thousand, seven hundred ninety-one".