191099220677 has 2 divisors, whose sum is σ = 191099220678. Its totient is φ = 191099220676.

The previous prime is 191099220607. The next prime is 191099220679. The reversal of 191099220677 is 776022990191.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 161821957441 + 29277263236 = 402271^2 + 171106^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-191099220677 is a prime.

Together with 191099220679, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191099220679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95549610338 + 95549610339.

It is an arithmetic number, because the mean of its divisors is an integer number (95549610339).

Almost surely, 2^191099220677 is an apocalyptic number.

It is an amenable number.

191099220677 is a deficient number, since it is larger than the sum of its proper divisors (1).

191099220677 is an equidigital number, since it uses as much as digits as its factorization.

191099220677 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 857304, while the sum is 53.

The spelling of 191099220677 in words is "one hundred ninety-one billion, ninety-nine million, two hundred twenty thousand, six hundred seventy-seven".