191540441 has 2 divisors, whose sum is σ = 191540442. Its totient is φ = 191540440.

The previous prime is 191540423. The next prime is 191540443. The reversal of 191540441 is 144045191.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 190550416 + 990025 = 13804^2 + 995^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-191540441 is a prime.

It is a Sophie Germain prime.

Together with 191540443, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (191540443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95770220 + 95770221.

It is an arithmetic number, because the mean of its divisors is an integer number (95770221).

Almost surely, 2^191540441 is an apocalyptic number.

It is an amenable number.

191540441 is a deficient number, since it is larger than the sum of its proper divisors (1).

191540441 is an equidigital number, since it uses as much as digits as its factorization.

191540441 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 191540441 is about 13839.8136186872. The cubic root of 191540441 is about 576.4391834802.

The spelling of 191540441 in words is "one hundred ninety-one million, five hundred forty thousand, four hundred forty-one".