191113261 has 2 divisors, whose sum is σ = 191113262. Its totient is φ = 191113260.

The previous prime is 191113253. The next prime is 191113289. The reversal of 191113261 is 162311191.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 161137636 + 29975625 = 12694^2 + 5475^2 .

It is a cyclic number.

It is not a de Polignac number, because 191113261 - 2³ = 191113253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191113231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95556630 + 95556631.

It is an arithmetic number, because the mean of its divisors is an integer number (95556631).

Almost surely, 2^191113261 is an apocalyptic number.

It is an amenable number.

191113261 is a deficient number, since it is larger than the sum of its proper divisors (1).

191113261 is an equidigital number, since it uses as much as digits as its factorization.

191113261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 324, while the sum is 25.

The square root of 191113261 is about 13824.3719929695. The cubic root of 191113261 is about 576.0103330917.

The spelling of 191113261 in words is "one hundred ninety-one million, one hundred thirteen thousand, two hundred sixty-one".