191868528791 has 2 divisors, whose sum is σ = 191868528792. Its totient is φ = 191868528790.

The previous prime is 191868528779. The next prime is 191868528821. The reversal of 191868528791 is 197825868191.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-191868528791 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191868524791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95934264395 + 95934264396.

It is an arithmetic number, because the mean of its divisors is an integer number (95934264396).

Almost surely, 2^191868528791 is an apocalyptic number.

191868528791 is a deficient number, since it is larger than the sum of its proper divisors (1).

191868528791 is an equidigital number, since it uses as much as digits as its factorization.

191868528791 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17418240, while the sum is 65.

The spelling of 191868528791 in words is "one hundred ninety-one billion, eight hundred sixty-eight million, five hundred twenty-eight thousand, seven hundred ninety-one".