904391 has 4 divisors (see below), whose sum is σ = 928872. Its totient is φ = 879912.

The previous prime is 904369. The next prime is 904399. The reversal of 904391 is 193409.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 904391 - 2¹⁰ = 903367 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 904391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (904399) 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, 12185 + ... + 12258.

It is an arithmetic number, because the mean of its divisors is an integer number (232218).

2⁹⁰⁴³⁹¹ is an apocalyptic number.

904391 is a deficient number, since it is larger than the sum of its proper divisors (24481).

904391 is a wasteful number, since it uses less digits than its factorization.

904391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24480.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 904391 is about 950.9947423619. The cubic root of 904391 is about 96.7057009750.

The spelling of 904391 in words is "nine hundred four thousand, three hundred ninety-one".