204406 has 4 divisors (see below), whose sum is σ = 306612. Its totient is φ = 102202.

The previous prime is 204397. The next prime is 204427. The reversal of 204406 is 604402.

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

It is a self number, because there is not a number n which added to its sum of digits gives 204406.

It is a congruent number.

It is an unprimeable number.

204406 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 as a sum of consecutive naturals, namely, 51100 + ... + 51103.

It is an arithmetic number, because the mean of its divisors is an integer number (76653).

2²⁰⁴⁴⁰⁶ is an apocalyptic number.

204406 is a deficient number, since it is larger than the sum of its proper divisors (102206).

204406 is a wasteful number, since it uses less digits than its factorization.

204406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102205.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 204406 is about 452.1128177789. The cubic root of 204406 is about 58.9066800141.

Adding to 204406 its reverse (604402), we get a palindrome (808808).

The spelling of 204406 in words is "two hundred four thousand, four hundred six".