191942887 has 2 divisors, whose sum is σ = 191942888. Its totient is φ = 191942886.

The previous prime is 191942831. The next prime is 191942893. The reversal of 191942887 is 788249191.

It is a strong prime.

It is an emirp because it is prime and its reverse (788249191) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 191942887 - 2⁷ = 191942759 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 191942887.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191942897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95971443 + 95971444.

It is an arithmetic number, because the mean of its divisors is an integer number (95971444).

Almost surely, 2^191942887 is an apocalyptic number.

191942887 is a deficient number, since it is larger than the sum of its proper divisors (1).

191942887 is an equidigital number, since it uses as much as digits as its factorization.

191942887 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 290304, while the sum is 49.

The square root of 191942887 is about 13854.3454193982. The cubic root of 191942887 is about 576.8426202281.

The spelling of 191942887 in words is "one hundred ninety-one million, nine hundred forty-two thousand, eight hundred eighty-seven".