12649728769 has 2 divisors, whose sum is σ = 12649728770. Its totient is φ = 12649728768.

The previous prime is 12649728733. The next prime is 12649728779. The reversal of 12649728769 is 96782794621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12379455169 + 270273600 = 111263^2 + 16440^2 .

It is a cyclic number.

It is not a de Polignac number, because 12649728769 - 2¹⁵ = 12649696001 is a prime.

It is a super-2 number, since 2×12649728769² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (12649728779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6324864384 + 6324864385.

It is an arithmetic number, because the mean of its divisors is an integer number (6324864385).

Almost surely, 2^12649728769 is an apocalyptic number.

It is an amenable number.

12649728769 is a deficient number, since it is larger than the sum of its proper divisors (1).

12649728769 is an equidigital number, since it uses as much as digits as its factorization.

12649728769 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18289152, while the sum is 61.

The spelling of 12649728769 in words is "twelve billion, six hundred forty-nine million, seven hundred twenty-eight thousand, seven hundred sixty-nine".