204591 has 8 divisors (see below), whose sum is σ = 278784. Its totient is φ = 133400.

The previous prime is 204587. The next prime is 204599. The reversal of 204591 is 195402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 204591 - 2² = 204587 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204599) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 585 + ... + 866.

It is an arithmetic number, because the mean of its divisors is an integer number (34848).

2²⁰⁴⁵⁹¹ is an apocalyptic number.

204591 is a deficient number, since it is larger than the sum of its proper divisors (74193).

204591 is a wasteful number, since it uses less digits than its factorization.

204591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1501.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 204591 is about 452.3173664586. The cubic root of 204591 is about 58.9244460447.

Adding to 204591 its reverse (195402), we get a palindrome (399993).

The spelling of 204591 in words is "two hundred four thousand, five hundred ninety-one".