191890189 has 2 divisors, whose sum is σ = 191890190. Its totient is φ = 191890188.

The previous prime is 191890183. The next prime is 191890213. The reversal of 191890189 is 981098191.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 182709289 + 9180900 = 13517^2 + 3030^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-191890189 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191890183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95945094 + 95945095.

It is an arithmetic number, because the mean of its divisors is an integer number (95945095).

Almost surely, 2^191890189 is an apocalyptic number.

It is an amenable number.

191890189 is a deficient number, since it is larger than the sum of its proper divisors (1).

191890189 is an equidigital number, since it uses as much as digits as its factorization.

191890189 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46656, while the sum is 46.

The square root of 191890189 is about 13852.4434306732. The cubic root of 191890189 is about 576.7898246019.

The spelling of 191890189 in words is "one hundred ninety-one million, eight hundred ninety thousand, one hundred eighty-nine".