128221025789 has 2 divisors, whose sum is σ = 128221025790. Its totient is φ = 128221025788.

The previous prime is 128221025783. The next prime is 128221025819. The reversal of 128221025789 is 987520122821.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 92344877689 + 35876148100 = 303883^2 + 189410^2 .

It is a cyclic number.

It is not a de Polignac number, because 128221025789 - 2²⁰ = 128219977213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128221025783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64110512894 + 64110512895.

It is an arithmetic number, because the mean of its divisors is an integer number (64110512895).

Almost surely, 2^128221025789 is an apocalyptic number.

It is an amenable number.

128221025789 is a deficient number, since it is larger than the sum of its proper divisors (1).

128221025789 is an equidigital number, since it uses as much as digits as its factorization.

128221025789 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 322560, while the sum is 47.

The spelling of 128221025789 in words is "one hundred twenty-eight billion, two hundred twenty-one million, twenty-five thousand, seven hundred eighty-nine".