128585657 has 2 divisors, whose sum is σ = 128585658. Its totient is φ = 128585656.

The previous prime is 128585629. The next prime is 128585683. The reversal of 128585657 is 756585821.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 92236816 + 36348841 = 9604^2 + 6029^2 .

It is an emirp because it is prime and its reverse (756585821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 128585657 - 2¹⁰ = 128584633 is a prime.

It is a super-2 number, since 2×128585657² = 33068542372243298, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (128585627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64292828 + 64292829.

It is an arithmetic number, because the mean of its divisors is an integer number (64292829).

Almost surely, 2^128585657 is an apocalyptic number.

It is an amenable number.

128585657 is a deficient number, since it is larger than the sum of its proper divisors (1).

128585657 is an equidigital number, since it uses as much as digits as its factorization.

128585657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 672000, while the sum is 47.

The square root of 128585657 is about 11339.5615876453. The cubic root of 128585657 is about 504.7358773072.

The spelling of 128585657 in words is "one hundred twenty-eight million, five hundred eighty-five thousand, six hundred fifty-seven".