191281 has 2 divisors, whose sum is σ = 191282. Its totient is φ = 191280.

The previous prime is 191251. The next prime is 191297. The reversal of 191281 is 182191.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 173056 + 18225 = 416^2 + 135^2 .

It is a cyclic number.

It is not a de Polignac number, because 191281 - 2⁵ = 191249 is a prime.

It is a super-2 number, since 2×191281² = 73176841922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (191231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95640 + 95641.

It is an arithmetic number, because the mean of its divisors is an integer number (95641).

2¹⁹¹²⁸¹ is an apocalyptic number.

It is an amenable number.

191281 is a deficient number, since it is larger than the sum of its proper divisors (1).

191281 is an equidigital number, since it uses as much as digits as its factorization.

191281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 144, while the sum is 22.

The square root of 191281 is about 437.3568337182. The cubic root of 191281 is about 57.6178804121.

The spelling of 191281 in words is "one hundred ninety-one thousand, two hundred eighty-one".