720761 has 4 divisors (see below), whose sum is σ = 722832. Its totient is φ = 718692.

The previous prime is 720743. The next prime is 720763. The reversal of 720761 is 167027.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 720761 - 2⁶ = 720697 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 720761.

It is not an unprimeable number, because it can be changed into a prime (720763) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 371 + ... + 1256.

It is an arithmetic number, because the mean of its divisors is an integer number (180708).

2⁷²⁰⁷⁶¹ is an apocalyptic number.

It is an amenable number.

720761 is a deficient number, since it is larger than the sum of its proper divisors (2071).

720761 is a wasteful number, since it uses less digits than its factorization.

720761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2070.

The product of its (nonzero) digits is 588, while the sum is 23.

The square root of 720761 is about 848.9764425471. The cubic root of 720761 is about 89.6596611182.

Adding to 720761 its reverse (167027), we get a palindrome (887788).

The spelling of 720761 in words is "seven hundred twenty thousand, seven hundred sixty-one".