28125128 has 16 divisors (see below), whose sum is σ = 54553500. Its totient is φ = 13577536.

The previous prime is 28125127. The next prime is 28125169. The reversal of 28125128 is 82152182.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 28111204 + 13924 = 5302^2 + 118^2 .

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a self number, because there is not a number n which added to its sum of digits gives 28125128.

It is not an unprimeable number, because it can be changed into a prime (28125127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60383 + ... + 60846.

Almost surely, 2^28125128 is an apocalyptic number.

It is an amenable number.

28125128 is a deficient number, since it is larger than the sum of its proper divisors (26428372).

28125128 is a wasteful number, since it uses less digits than its factorization.

28125128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121264 (or 121260 counting only the distinct ones).

The product of its digits is 2560, while the sum is 29.

The square root of 28125128 is about 5303.3129268411. The cubic root of 28125128 is about 304.1105611243.

The spelling of 28125128 in words is "twenty-eight million, one hundred twenty-five thousand, one hundred twenty-eight".