904309 has 4 divisors (see below), whose sum is σ = 1033504. Its totient is φ = 775116.

The previous prime is 904303. The next prime is 904357. The reversal of 904309 is 903409.

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, and also an emirpimes, since its reverse is a distinct semiprime: 903409 = 13 ⋅69493.

It is a cyclic number.

It is not a de Polignac number, because 904309 - 2⁷ = 904181 is a prime.

It is a Duffinian number.

904309 is a lucky number.

It is a nialpdrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (904303) 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, 64587 + ... + 64600.

It is an arithmetic number, because the mean of its divisors is an integer number (258376).

2⁹⁰⁴³⁰⁹ is an apocalyptic number.

It is an amenable number.

904309 is a deficient number, since it is larger than the sum of its proper divisors (129195).

904309 is a wasteful number, since it uses less digits than its factorization.

904309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129194.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 904309 is about 950.9516286331. The cubic root of 904309 is about 96.7027781584.

Subtracting from 904309 its reverse (903409), we obtain a square (900 = 30²).

The spelling of 904309 in words is "nine hundred four thousand, three hundred nine".