731040 has 48 divisors (see below), whose sum is σ = 2304288. Its totient is φ = 194816.

The previous prime is 731033. The next prime is 731041. The reversal of 731040 is 40137.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an Ulam number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 731040.

It is not an unprimeable number, because it can be changed into a prime (731041) by changing a digit.

731040 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 282 + ... + 1241.

It is an arithmetic number, because the mean of its divisors is an integer number (48006).

2⁷³¹⁰⁴⁰ is an apocalyptic number.

It is an amenable number.

731040 is an abundant number, since it is smaller than the sum of its proper divisors (1573248).

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

731040 is a wasteful number, since it uses less digits than its factorization.

731040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1541 (or 1533 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 15.

The square root of 731040 is about 855.0087718848. The cubic root of 731040 is about 90.0838724310.

Subtracting from 731040 its sum of digits (15), we obtain a square (731025 = 855²).

Adding to 731040 its reverse (40137), we get a palindrome (771177).

The spelling of 731040 in words is "seven hundred thirty-one thousand, forty".