12728645689 has 2 divisors, whose sum is σ = 12728645690. Its totient is φ = 12728645688.

The previous prime is 12728645659. The next prime is 12728645701. The reversal of 12728645689 is 98654682721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11966609664 + 762036025 = 109392^2 + 27605^2 .

It is a cyclic number.

It is not a de Polignac number, because 12728645689 - 2⁷ = 12728645561 is a prime.

It is not a weakly prime, because it can be changed into another prime (12728645659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6364322844 + 6364322845.

It is an arithmetic number, because the mean of its divisors is an integer number (6364322845).

Almost surely, 2^12728645689 is an apocalyptic number.

It is an amenable number.

12728645689 is a deficient number, since it is larger than the sum of its proper divisors (1).

12728645689 is an equidigital number, since it uses as much as digits as its factorization.

12728645689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11612160, while the sum is 58.

The spelling of 12728645689 in words is "twelve billion, seven hundred twenty-eight million, six hundred forty-five thousand, six hundred eighty-nine".