128318857 has 2 divisors, whose sum is σ = 128318858. Its totient is φ = 128318856.

The previous prime is 128318851. The next prime is 128318867. The reversal of 128318857 is 758813821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 122345721 + 5973136 = 11061^2 + 2444^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128318857 is a prime.

It is not a weakly prime, because it can be changed into another prime (128318851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64159428 + 64159429.

It is an arithmetic number, because the mean of its divisors is an integer number (64159429).

Almost surely, 2^128318857 is an apocalyptic number.

It is an amenable number.

128318857 is a deficient number, since it is larger than the sum of its proper divisors (1).

128318857 is an equidigital number, since it uses as much as digits as its factorization.

128318857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 107520, while the sum is 43.

The square root of 128318857 is about 11327.7913557763. The cubic root of 128318857 is about 504.3865465455.

The spelling of 128318857 in words is "one hundred twenty-eight million, three hundred eighteen thousand, eight hundred fifty-seven".