28275228 has 18 divisors (see below), whose sum is σ = 71473584. Its totient is φ = 9425064.

The previous prime is 28275227. The next prime is 28275239. The reversal of 28275228 is 82257282.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 785423 = 28275228 / (2 + 8 + 2 + 7 + 5 + 2 + 2 + 8).

It is a junction number, because it is equal to n+sod(n) for n = 28275192 and 28275201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28275223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 392676 + ... + 392747.

Almost surely, 2^28275228 is an apocalyptic number.

It is an amenable number.

28275228 is an abundant number, since it is smaller than the sum of its proper divisors (43198356).

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

28275228 is a wasteful number, since it uses less digits than its factorization.

28275228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 785433 (or 785428 counting only the distinct ones).

The product of its digits is 35840, while the sum is 36.

The square root of 28275228 is about 5317.4456273666. The cubic root of 28275228 is about 304.6506005176.

The spelling of 28275228 in words is "twenty-eight million, two hundred seventy-five thousand, two hundred twenty-eight".