904409 has 4 divisors (see below), whose sum is σ = 986640. Its totient is φ = 822180.

The previous prime is 904399. The next prime is 904441.

904409 = 83² + 84² + ... + 148².

904409 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-904409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (904459) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41099 + ... + 41120.

It is an arithmetic number, because the mean of its divisors is an integer number (246660).

2⁹⁰⁴⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

904409 is a deficient number, since it is larger than the sum of its proper divisors (82231).

904409 is a wasteful number, since it uses less digits than its factorization.

904409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82230.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 904409 is about 951.0042060895. The cubic root of 904409 is about 96.7063425453.

The spelling of 904409 in words is "nine hundred four thousand, four hundred nine".