128665237 has 2 divisors, whose sum is σ = 128665238. Its totient is φ = 128665236.

The previous prime is 128665219. The next prime is 128665267. The reversal of 128665237 is 732566821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 116769636 + 11895601 = 10806^2 + 3449^2 .

It is a cyclic number.

It is not a de Polignac number, because 128665237 - 2¹¹ = 128663189 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 128665237.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128665217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64332618 + 64332619.

It is an arithmetic number, because the mean of its divisors is an integer number (64332619).

Almost surely, 2^128665237 is an apocalyptic number.

It is an amenable number.

128665237 is a deficient number, since it is larger than the sum of its proper divisors (1).

128665237 is an equidigital number, since it uses as much as digits as its factorization.

128665237 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 120960, while the sum is 40.

The square root of 128665237 is about 11343.0699989024. The cubic root of 128665237 is about 504.8399806695.

The spelling of 128665237 in words is "one hundred twenty-eight million, six hundred sixty-five thousand, two hundred thirty-seven".