209404 has 12 divisors (see below), whose sum is σ = 394744. Its totient is φ = 96624.

The previous prime is 209401. The next prime is 209431. The reversal of 209404 is 404902.

209404 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (19) coincides with the sum of the digits of its distinct prime factors.

It is an Ulam number.

It is a plaindrome in base 11.

It is a nialpdrome in base 13.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209401) 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 3 ways as a sum of consecutive naturals, for example, 1962 + ... + 2065.

2²⁰⁹⁴⁰⁴ is an apocalyptic number.

It is an amenable number.

209404 is a deficient number, since it is larger than the sum of its proper divisors (185340).

209404 is a wasteful number, since it uses less digits than its factorization.

209404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4044 (or 4042 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 209404 is about 457.6068181310. The cubic root of 209404 is about 59.3829348583.

The spelling of 209404 in words is "two hundred nine thousand, four hundred four".