731904 has 36 divisors (see below), whose sum is σ = 1949976. Its totient is φ = 243712.

The previous prime is 731893. The next prime is 731909. The reversal of 731904 is 409137.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (731909) by changing a digit.

731904 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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, 292 + ... + 1244.

It is an arithmetic number, because the mean of its divisors is an integer number (54166).

2⁷³¹⁹⁰⁴ 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 731904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (974988).

731904 is an abundant number, since it is smaller than the sum of its proper divisors (1218072).

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

731904 is an equidigital number, since it uses as much as digits as its factorization.

731904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 972 (or 958 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 24.

The square root of 731904 is about 855.5138806589. The cubic root of 731904 is about 90.1193478373.

The spelling of 731904 in words is "seven hundred thirty-one thousand, nine hundred four".