191634493 has 2 divisors, whose sum is σ = 191634494. Its totient is φ = 191634492.

The previous prime is 191634439. The next prime is 191634497. The reversal of 191634493 is 394436191.

Together with previous prime (191634439) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 108951844 + 82682649 = 10438^2 + 9093^2 .

It is an emirp because it is prime and its reverse (394436191) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 191634493 - 2¹⁷ = 191503421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191634497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95817246 + 95817247.

It is an arithmetic number, because the mean of its divisors is an integer number (95817247).

Almost surely, 2^191634493 is an apocalyptic number.

It is an amenable number.

191634493 is a deficient number, since it is larger than the sum of its proper divisors (1).

191634493 is an equidigital number, since it uses as much as digits as its factorization.

191634493 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69984, while the sum is 40.

The square root of 191634493 is about 13843.2110798037. The cubic root of 191634493 is about 576.5335175826.

The spelling of 191634493 in words is "one hundred ninety-one million, six hundred thirty-four thousand, four hundred ninety-three".