720565 has 8 divisors (see below), whose sum is σ = 870048. Its totient is φ = 572880.

The previous prime is 720547. The next prime is 720569. The reversal of 720565 is 565027.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 720565 - 2⁹ = 720053 is a prime.

It is a Duffinian number.

720565 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720569) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 714 + ... + 1396.

It is an arithmetic number, because the mean of its divisors is an integer number (108756).

2⁷²⁰⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

720565 is a deficient number, since it is larger than the sum of its proper divisors (149483).

720565 is a wasteful number, since it uses less digits than its factorization.

720565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 899.

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 720565 is about 848.8610015780. The cubic root of 720565 is about 89.6515331873.

The spelling of 720565 in words is "seven hundred twenty thousand, five hundred sixty-five".