597991 has 4 divisors (see below), whose sum is σ = 604800. Its totient is φ = 591184.

The previous prime is 597967. The next prime is 597997. The reversal of 597991 is 199795.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 597991 - 2¹¹ = 595943 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (597997) 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 in 3 ways as a sum of consecutive naturals, for example, 3271 + ... + 3448.

It is an arithmetic number, because the mean of its divisors is an integer number (151200).

2⁵⁹⁷⁹⁹¹ is an apocalyptic number.

597991 is a deficient number, since it is larger than the sum of its proper divisors (6809).

597991 is an equidigital number, since it uses as much as digits as its factorization.

597991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6808.

The product of its digits is 25515, while the sum is 40.

The square root of 597991 is about 773.2987779636. The cubic root of 597991 is about 84.2490248106.

The spelling of 597991 in words is "five hundred ninety-seven thousand, nine hundred ninety-one".