128209373209 has 2 divisors, whose sum is σ = 128209373210. Its totient is φ = 128209373208.

The previous prime is 128209373177. The next prime is 128209373213. The reversal of 128209373209 is 902373902821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 128135361600 + 74011609 = 357960^2 + 8603^2 .

It is a cyclic number.

It is not a de Polignac number, because 128209373209 - 2⁵ = 128209373177 is a prime.

It is not a weakly prime, because it can be changed into another prime (128209373219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64104686604 + 64104686605.

It is an arithmetic number, because the mean of its divisors is an integer number (64104686605).

Almost surely, 2^128209373209 is an apocalyptic number.

It is an amenable number.

128209373209 is a deficient number, since it is larger than the sum of its proper divisors (1).

128209373209 is an equidigital number, since it uses as much as digits as its factorization.

128209373209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 326592, while the sum is 46.

The spelling of 128209373209 in words is "one hundred twenty-eight billion, two hundred nine million, three hundred seventy-three thousand, two hundred nine".