724840 has 16 divisors (see below), whose sum is σ = 1630980. Its totient is φ = 289920.

The previous prime is 724837. The next prime is 724847. The reversal of 724840 is 48427.

724840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 708964 + 15876 = 842^2 + 126^2 .

It is not an unprimeable number, because it can be changed into a prime (724847) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9021 + ... + 9100.

2⁷²⁴⁸⁴⁰ is an apocalyptic number.

It is an amenable number.

724840 is an abundant number, since it is smaller than the sum of its proper divisors (906140).

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

724840 is a wasteful number, since it uses less digits than its factorization.

724840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18132 (or 18128 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 25.

The square root of 724840 is about 851.3753578769. The cubic root of 724840 is about 89.8284799127.

The spelling of 724840 in words is "seven hundred twenty-four thousand, eight hundred forty".