904991 has 4 divisors (see below), whose sum is σ = 906984. Its totient is φ = 903000.

The previous prime is 904987. The next prime is 904997. The reversal of 904991 is 199409.

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 904991 - 2² = 904987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 904991.

It is not an unprimeable number, because it can be changed into a prime (904997) 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, 56 + ... + 1346.

It is an arithmetic number, because the mean of its divisors is an integer number (226746).

2⁹⁰⁴⁹⁹¹ is an apocalyptic number.

904991 is a deficient number, since it is larger than the sum of its proper divisors (1993).

904991 is a wasteful number, since it uses less digits than its factorization.

904991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1992.

The product of its (nonzero) digits is 2916, while the sum is 32.

The square root of 904991 is about 951.3101492153. The cubic root of 904991 is about 96.7270820642.

The spelling of 904991 in words is "nine hundred four thousand, nine hundred ninety-one".