720856 has 8 divisors (see below), whose sum is σ = 1351620. Its totient is φ = 360424.

The previous prime is 720847. The next prime is 720857. The reversal of 720856 is 658027.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45046 + ... + 45061.

2⁷²⁰⁸⁵⁶ is an apocalyptic number.

It is an amenable number.

720856 is a deficient number, since it is larger than the sum of its proper divisors (630764).

720856 is a wasteful number, since it uses less digits than its factorization.

720856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90113 (or 90109 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 720856 is about 849.0323904304. The cubic root of 720856 is about 89.6636001463.

The spelling of 720856 in words is "seven hundred twenty thousand, eight hundred fifty-six".