921904 has 20 divisors (see below), whose sum is σ = 1802464. Its totient is φ = 456768.

The previous prime is 921901. The next prime is 921911. The reversal of 921904 is 409129.

It is not an unprimeable number, because it can be changed into a prime (921901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2329 + ... + 2695.

2⁹²¹⁹⁰⁴ is an apocalyptic number.

It is an amenable number.

921904 is a deficient number, since it is larger than the sum of its proper divisors (880560).

921904 is a wasteful number, since it uses less digits than its factorization.

921904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 532 (or 526 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 921904 is about 960.1583202785. The cubic root of 921904 is about 97.3259309230.

It can be divided in two parts, 9 and 21904, that multiplied together give a square (197136 = 444²).

The spelling of 921904 in words is "nine hundred twenty-one thousand, nine hundred four".