210904 has 16 divisors (see below), whose sum is σ = 405720. Its totient is φ = 102720.

The previous prime is 210901. The next prime is 210907. The reversal of 210904 is 409012.

210904 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (210901) and next prime (210907).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7 + ... + 649.

2²¹⁰⁹⁰⁴ is an apocalyptic number.

It is an amenable number.

210904 is a deficient number, since it is larger than the sum of its proper divisors (194816).

210904 is a wasteful number, since it uses less digits than its factorization.

210904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 690 (or 686 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 210904 is about 459.2428551431. The cubic root of 210904 is about 59.5243879969.

Adding to 210904 its reverse (409012), we get a palindrome (619916).

The spelling of 210904 in words is "two hundred ten thousand, nine hundred four".