13012721 has 2 divisors, whose sum is σ = 13012722. Its totient is φ = 13012720.

The previous prime is 13012717. The next prime is 13012723. The reversal of 13012721 is 12721031.

13012721 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10336225 + 2676496 = 3215^2 + 1636^2 .

It is a cyclic number.

It is not a de Polignac number, because 13012721 - 2² = 13012717 is a prime.

Together with 13012723, it forms a pair of twin primes.

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 13012721.

It is not a weakly prime, because it can be changed into another prime (13012723) 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, 6506360 + 6506361.

It is an arithmetic number, because the mean of its divisors is an integer number (6506361).

Almost surely, 2^13012721 is an apocalyptic number.

It is an amenable number.

13012721 is a deficient number, since it is larger than the sum of its proper divisors (1).

13012721 is an equidigital number, since it uses as much as digits as its factorization.

13012721 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 13012721 is about 3607.3149294177. The cubic root of 13012721 is about 235.2101394834.

Adding to 13012721 its reverse (12721031), we get a palindrome (25733752).

The spelling of 13012721 in words is "thirteen million, twelve thousand, seven hundred twenty-one".