9721013 has 2 divisors, whose sum is σ = 9721014. Its totient is φ = 9721012.

The previous prime is 9720959. The next prime is 9721031. The reversal of 9721013 is 3101279.

Together with next prime (9721031) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6061444 + 3659569 = 2462^2 + 1913^2 .

It is an emirp because it is prime and its reverse (3101279) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9721013 - 2⁸ = 9720757 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 9721013.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9721513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4860506 + 4860507.

It is an arithmetic number, because the mean of its divisors is an integer number (4860507).

Almost surely, 2^9721013 is an apocalyptic number.

It is an amenable number.

9721013 is a deficient number, since it is larger than the sum of its proper divisors (1).

9721013 is an equidigital number, since it uses as much as digits as its factorization.

9721013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 378, while the sum is 23.

The square root of 9721013 is about 3117.8539093421. The cubic root of 9721013 is about 213.4210118656.

The spelling of 9721013 in words is "nine million, seven hundred twenty-one thousand, thirteen".