191995847 has 2 divisors, whose sum is σ = 191995848. Its totient is φ = 191995846.

The previous prime is 191995831. The next prime is 191995861. The reversal of 191995847 is 748599191.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 191995847 - 2⁴ = 191995831 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191995877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95997923 + 95997924.

It is an arithmetic number, because the mean of its divisors is an integer number (95997924).

Almost surely, 2^191995847 is an apocalyptic number.

191995847 is a deficient number, since it is larger than the sum of its proper divisors (1).

191995847 is an equidigital number, since it uses as much as digits as its factorization.

191995847 is an evil number, because the sum of its binary digits is even.

The product of its digits is 816480, while the sum is 53.

The square root of 191995847 is about 13856.2566012614. The cubic root of 191995847 is about 576.8956686051.

The spelling of 191995847 in words is "one hundred ninety-one million, nine hundred ninety-five thousand, eight hundred forty-seven".