12728645693 has 16 divisors (see below), whose sum is σ = 13514074560. Its totient is φ = 11967446400.

The previous prime is 12728645689. The next prime is 12728645701. The reversal of 12728645693 is 39654682721.

It is a cyclic number.

It is not a de Polignac number, because 12728645693 - 2² = 12728645689 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12728645393) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 640598 + ... + 660168.

It is an arithmetic number, because the mean of its divisors is an integer number (844629660).

Almost surely, 2^12728645693 is an apocalyptic number.

It is an amenable number.

12728645693 is a deficient number, since it is larger than the sum of its proper divisors (785428867).

12728645693 is a wasteful number, since it uses less digits than its factorization.

12728645693 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20188.

The product of its digits is 4354560, while the sum is 53.

The spelling of 12728645693 in words is "twelve billion, seven hundred twenty-eight million, six hundred forty-five thousand, six hundred ninety-three".