28128276 has 48 divisors (see below), whose sum is σ = 79558080. Its totient is φ = 8523360.

The previous prime is 28128271. The next prime is 28128307. The reversal of 28128276 is 67282182.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 28128276.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28128271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10651 + ... + 13026.

It is an arithmetic number, because the mean of its divisors is an integer number (1657460).

Almost surely, 2^28128276 is an apocalyptic number.

It is an amenable number.

28128276 is an abundant number, since it is smaller than the sum of its proper divisors (51429804).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28128276 is a wasteful number, since it uses less digits than its factorization.

28128276 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23701 (or 23693 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

The square root of 28128276 is about 5303.6097141475. The cubic root of 28128276 is about 304.1219069017.

The spelling of 28128276 in words is "twenty-eight million, one hundred twenty-eight thousand, two hundred seventy-six".