12726862721 has 4 divisors (see below), whose sum is σ = 12727550292. Its totient is φ = 12726175152.

The previous prime is 12726862717. The next prime is 12726862723.

12726862721 is nontrivially palindromic in base 10.

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

It can be written as a sum of positive squares in 2 ways, for example, as 651270400 + 12075592321 = 25520^2 + 109889^2 .

It is a cyclic number.

It is not a de Polignac number, because 12726862721 - 2² = 12726862717 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12726862723) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 315230 + ... + 353303.

It is an arithmetic number, because the mean of its divisors is an integer number (3181887573).

Almost surely, 2^12726862721 is an apocalyptic number.

It is an amenable number.

12726862721 is a deficient number, since it is larger than the sum of its proper divisors (687571).

12726862721 is an equidigital number, since it uses as much as digits as its factorization.

12726862721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 687570.

The product of its digits is 225792, while the sum is 44.

The spelling of 12726862721 in words is "twelve billion, seven hundred twenty-six million, eight hundred sixty-two thousand, seven hundred twenty-one".