720724 has 6 divisors (see below), whose sum is σ = 1261274. Its totient is φ = 360360.

The previous prime is 720703. The next prime is 720743. The reversal of 720724 is 427027.

It can be written as a sum of positive squares in only one way, i.e., 535824 + 184900 = 732^2 + 430^2 .

It is a junction number, because it is equal to n+sod(n) for n = 720695 and 720704.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90087 + ... + 90094.

2⁷²⁰⁷²⁴ is an apocalyptic number.

It is an amenable number.

720724 is a deficient number, since it is larger than the sum of its proper divisors (540550).

720724 is a wasteful number, since it uses less digits than its factorization.

720724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180185 (or 180183 counting only the distinct ones).

The product of its (nonzero) digits is 784, while the sum is 22.

The square root of 720724 is about 848.9546513213. The cubic root of 720724 is about 89.6581268767.

It can be divided in two parts, 720 and 724, that added together give a square (1444 = 38²).

The spelling of 720724 in words is "seven hundred twenty thousand, seven hundred twenty-four", and thus it is an iban number.