9720811 has 4 divisors (see below), whose sum is σ = 9730224. Its totient is φ = 9711400.

The previous prime is 9720803. The next prime is 9720817. The reversal of 9720811 is 1180279.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 9720811 - 2³ = 9720803 is a prime.

It is a super-3 number, since 3×9720811³ (a number of 22 digits) contains 333 as substring.

It is a Duffinian number.

9720811 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 9720811.

It is not an unprimeable number, because it can be changed into a prime (9720817) 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, 2935 + ... + 5296.

It is an arithmetic number, because the mean of its divisors is an integer number (2432556).

Almost surely, 2^9720811 is an apocalyptic number.

9720811 is a deficient number, since it is larger than the sum of its proper divisors (9413).

9720811 is a wasteful number, since it uses less digits than its factorization.

9720811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9412.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 9720811 is about 3117.8215150967. The cubic root of 9720811 is about 213.4195335786.

The spelling of 9720811 in words is "nine million, seven hundred twenty thousand, eight hundred eleven".