12310721 has 2 divisors, whose sum is σ = 12310722. Its totient is φ = 12310720.

The previous prime is 12310699. The next prime is 12310733. The reversal of 12310721 is 12701321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10240000 + 2070721 = 3200^2 + 1439^2 .

It is an emirp because it is prime and its reverse (12701321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12310721 - 2⁶ = 12310657 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12310721.

It is not a weakly prime, because it can be changed into another prime (12310741) 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 as a sum of consecutive naturals, namely, 6155360 + 6155361.

It is an arithmetic number, because the mean of its divisors is an integer number (6155361).

Almost surely, 2^12310721 is an apocalyptic number.

It is an amenable number.

12310721 is a deficient number, since it is larger than the sum of its proper divisors (1).

12310721 is an equidigital number, since it uses as much as digits as its factorization.

12310721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 12310721 is about 3508.6637057433. The cubic root of 12310721 is about 230.9020717697.

It can be divided in two parts, 12310 and 721, that added together give a palindrome (13031).

The spelling of 12310721 in words is "twelve million, three hundred ten thousand, seven hundred twenty-one".