128668525 has 6 divisors (see below), whose sum is σ = 159549002. Its totient is φ = 102934800.

The previous prime is 128668523. The next prime is 128668549. The reversal of 128668525 is 525866821.

It can be written as a sum of positive squares in 3 ways, for example, as 8590761 + 120077764 = 2931^2 + 10958^2 .

It is not a de Polignac number, because 128668525 - 2¹ = 128668523 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128668523) 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 in 5 ways as a sum of consecutive naturals, for example, 2573346 + ... + 2573395.

Almost surely, 2^128668525 is an apocalyptic number.

It is an amenable number.

128668525 is a deficient number, since it is larger than the sum of its proper divisors (30880477).

128668525 is an equidigital number, since it uses as much as digits as its factorization.

128668525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5146751 (or 5146746 counting only the distinct ones).

The product of its digits is 230400, while the sum is 43.

The square root of 128668525 is about 11343.2149322844. The cubic root of 128668525 is about 504.8442809756.

The spelling of 128668525 in words is "one hundred twenty-eight million, six hundred sixty-eight thousand, five hundred twenty-five".