720911 has 4 divisors (see below), whose sum is σ = 745800. Its totient is φ = 696024.

The previous prime is 720901. The next prime is 720913. The reversal of 720911 is 119027.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 720911 - 2⁶ = 720847 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 720911.

It is not an unprimeable number, because it can be changed into a prime (720913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12401 + ... + 12458.

It is an arithmetic number, because the mean of its divisors is an integer number (186450).

2⁷²⁰⁹¹¹ is an apocalyptic number.

720911 is a deficient number, since it is larger than the sum of its proper divisors (24889).

720911 is a wasteful number, since it uses less digits than its factorization.

720911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24888.

The product of its (nonzero) digits is 126, while the sum is 20.

The square root of 720911 is about 849.0647796252. The cubic root of 720911 is about 89.6658804781.

Adding to 720911 its reverse (119027), we get a palindrome (839938).

The spelling of 720911 in words is "seven hundred twenty thousand, nine hundred eleven".