999904 has 12 divisors (see below), whose sum is σ = 1968624. Its totient is φ = 499936.

The previous prime is 999883. The next prime is 999907. The reversal of 999904 is 409999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15592 + ... + 15655.

It is an arithmetic number, because the mean of its divisors is an integer number (164052).

2⁹⁹⁹⁹⁰⁴ is an apocalyptic number.

It is an amenable number.

999904 is a deficient number, since it is larger than the sum of its proper divisors (968720).

999904 is a wasteful number, since it uses less digits than its factorization.

999904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31257 (or 31249 counting only the distinct ones).

The product of its (nonzero) digits is 26244, while the sum is 40.

The square root of 999904 is about 999.9519988479. The cubic root of 999904 is about 99.9967998976.

The spelling of 999904 in words is "nine hundred ninety-nine thousand, nine hundred four".