204491 has 8 divisors (see below), whose sum is σ = 236544. Its totient is φ = 173160.

The previous prime is 204487. The next prime is 204509. The reversal of 204491 is 194402.

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 204491 - 2² = 204487 is a prime.

It is a super-3 number, since 3×204491³ = 25653336083828313, which contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (204431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 806 + ... + 1028.

It is an arithmetic number, because the mean of its divisors is an integer number (29568).

2²⁰⁴⁴⁹¹ is an apocalyptic number.

204491 is a deficient number, since it is larger than the sum of its proper divisors (32053).

204491 is a wasteful number, since it uses less digits than its factorization.

204491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 204491 is about 452.2068110942. The cubic root of 204491 is about 58.9148441154.

Adding to 204491 its reverse (194402), we get a palindrome (398893).

The spelling of 204491 in words is "two hundred four thousand, four hundred ninety-one".