591716921 has 2 divisors, whose sum is σ = 591716922. Its totient is φ = 591716920.

The previous prime is 591716863. The next prime is 591716927. The reversal of 591716921 is 129617195.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 297079696 + 294637225 = 17236^2 + 17165^2 .

It is a cyclic number.

It is not a de Polignac number, because 591716921 - 2¹⁴ = 591700537 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (591716927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 295858460 + 295858461.

It is an arithmetic number, because the mean of its divisors is an integer number (295858461).

Almost surely, 2^591716921 is an apocalyptic number.

It is an amenable number.

591716921 is a deficient number, since it is larger than the sum of its proper divisors (1).

591716921 is an equidigital number, since it uses as much as digits as its factorization.

591716921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34020, while the sum is 41.

The square root of 591716921 is about 24325.2321879977. The cubic root of 591716921 is about 839.5334337385.

The spelling of 591716921 in words is "five hundred ninety-one million, seven hundred sixteen thousand, nine hundred twenty-one".