720709 has 4 divisors (see below), whose sum is σ = 786240. Its totient is φ = 655180.

The previous prime is 720703. The next prime is 720743. The reversal of 720709 is 907027.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 907027 = 11 ⋅82457.

It is a cyclic number.

It is not a de Polignac number, because 720709 - 2⁵ = 720677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720703) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 32749 + ... + 32770.

It is an arithmetic number, because the mean of its divisors is an integer number (196560).

2⁷²⁰⁷⁰⁹ is an apocalyptic number.

It is an amenable number.

720709 is a deficient number, since it is larger than the sum of its proper divisors (65531).

720709 is a wasteful number, since it uses less digits than its factorization.

720709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65530.

The product of its (nonzero) digits is 882, while the sum is 25.

The square root of 720709 is about 848.9458168811. The cubic root of 720709 is about 89.6575048720.

The spelling of 720709 in words is "seven hundred twenty thousand, seven hundred nine".