199865948608091 has 2 divisors, whose sum is σ = 199865948608092. Its totient is φ = 199865948608090.

The previous prime is 199865948608021. The next prime is 199865948608189. The reversal of 199865948608091 is 190806849568991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 199865948608091 - 2³⁸ = 199591070701147 is a prime.

It is not a weakly prime, because it can be changed into another prime (199865948608021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99932974304045 + 99932974304046.

It is an arithmetic number, because the mean of its divisors is an integer number (99932974304046).

Almost surely, 2^{199865948608091} is an apocalyptic number.

199865948608091 is a deficient number, since it is larger than the sum of its proper divisors (1).

199865948608091 is an equidigital number, since it uses as much as digits as its factorization.

199865948608091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2418647040, while the sum is 83.

The spelling of 199865948608091 in words is "one hundred ninety-nine trillion, eight hundred sixty-five billion, nine hundred forty-eight million, six hundred eight thousand, ninety-one".