128811257 has 2 divisors, whose sum is σ = 128811258. Its totient is φ = 128811256.

The previous prime is 128811197. The next prime is 128811271. The reversal of 128811257 is 752118821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 108597241 + 20214016 = 10421^2 + 4496^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128811257 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (128811857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64405628 + 64405629.

It is an arithmetic number, because the mean of its divisors is an integer number (64405629).

Almost surely, 2^128811257 is an apocalyptic number.

It is an amenable number.

128811257 is a deficient number, since it is larger than the sum of its proper divisors (1).

128811257 is an equidigital number, since it uses as much as digits as its factorization.

128811257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8960, while the sum is 35.

The square root of 128811257 is about 11349.5047028494. The cubic root of 128811257 is about 505.0308865859.

The spelling of 128811257 in words is "one hundred twenty-eight million, eight hundred eleven thousand, two hundred fifty-seven".