909904 has 40 divisors (see below), whose sum is σ = 1908360. Its totient is φ = 419328.

The previous prime is 909901. The next prime is 909907. The reversal of 909904 is 409909.

It is an interprime number because it is at equal distance from previous prime (909901) and next prime (909907).

It can be written as a sum of positive squares in 4 ways, for example, as 419904 + 490000 = 648^2 + 700^2 .

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (909901) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17142 + ... + 17194.

It is an arithmetic number, because the mean of its divisors is an integer number (47709).

2⁹⁰⁹⁹⁰⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 909904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (954180).

909904 is an abundant number, since it is smaller than the sum of its proper divisors (998456).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

909904 is a wasteful number, since it uses less digits than its factorization.

909904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127 (or 121 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 909904 is about 953.8888824177. Note that the first 5 decimals coincide. The cubic root of 909904 is about 96.9018030587.

The spelling of 909904 in words is "nine hundred nine thousand, nine hundred four".