28128867 has 24 divisors (see below), whose sum is σ = 41065200. Its totient is φ = 17117568.

The previous prime is 28128853. The next prime is 28128883. The reversal of 28128867 is 76882182.

It is not a de Polignac number, because 28128867 - 2¹² = 28124771 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28128827) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55009 + ... + 55517.

It is an arithmetic number, because the mean of its divisors is an integer number (1711050).

Almost surely, 2^28128867 is an apocalyptic number.

28128867 is a deficient number, since it is larger than the sum of its proper divisors (12936333).

28128867 is a wasteful number, since it uses less digits than its factorization.

28128867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 647 (or 634 counting only the distinct ones).

The product of its digits is 86016, while the sum is 42.

The square root of 28128867 is about 5303.6654306244. The cubic root of 28128867 is about 304.1240368437.

The spelling of 28128867 in words is "twenty-eight million, one hundred twenty-eight thousand, eight hundred sixty-seven".