128663447576809 has 2 divisors, whose sum is σ = 128663447576810. Its totient is φ = 128663447576808.

The previous prime is 128663447576789. The next prime is 128663447576821. The reversal of 128663447576809 is 908675744366821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 92554501275625 + 36108946301184 = 9620525^2 + 6009072^2 .

It is a cyclic number.

It is not a de Polignac number, because 128663447576809 - 2¹⁵ = 128663447544041 is a prime.

It is not a weakly prime, because it can be changed into another prime (128663447576309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64331723788404 + 64331723788405.

It is an arithmetic number, because the mean of its divisors is an integer number (64331723788405).

It is a 1-persistent number, because it is pandigital, but 2⋅128663447576809 = 257326895153618 is not.

Almost surely, 2^{128663447576809} is an apocalyptic number.

It is an amenable number.

128663447576809 is a deficient number, since it is larger than the sum of its proper divisors (1).

128663447576809 is an equidigital number, since it uses as much as digits as its factorization.

128663447576809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2926264320, while the sum is 76.

The spelling of 128663447576809 in words is "one hundred twenty-eight trillion, six hundred sixty-three billion, four hundred forty-seven million, five hundred seventy-six thousand, eight hundred nine".