720520 has 16 divisors (see below), whose sum is σ = 1621260. Its totient is φ = 288192.

The previous prime is 720497. The next prime is 720527. The reversal of 720520 is 25027.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 695556 + 24964 = 834^2 + 158^2 .

It is a junction number, because it is equal to n+sod(n) for n = 720494 and 720503.

It is not an unprimeable number, because it can be changed into a prime (720527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8967 + ... + 9046.

2⁷²⁰⁵²⁰ is an apocalyptic number.

It is an amenable number.

720520 is an abundant number, since it is smaller than the sum of its proper divisors (900740).

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

720520 is a wasteful number, since it uses less digits than its factorization.

720520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18024 (or 18020 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 16.

The square root of 720520 is about 848.8344950578. The cubic root of 720520 is about 89.6496668727.

Adding to 720520 its reverse (25027), we get a palindrome (745547).

It can be divided in two parts, 7205 and 20, that added together give a square (7225 = 85²).

The spelling of 720520 in words is "seven hundred twenty thousand, five hundred twenty".