28256388 has 24 divisors (see below), whose sum is σ = 66151008. Its totient is φ = 9387456.

The previous prime is 28256381. The next prime is 28256399. The reversal of 28256388 is 88365282.

It is not an unprimeable number, because it can be changed into a prime (28256381) 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 7 ways as a sum of consecutive naturals, for example, 6 + ... + 7517.

It is an arithmetic number, because the mean of its divisors is an integer number (2756292).

Almost surely, 2^28256388 is an apocalyptic number.

It is an amenable number.

28256388 is an abundant number, since it is smaller than the sum of its proper divisors (37894620).

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

28256388 is a wasteful number, since it uses less digits than its factorization.

28256388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7843 (or 7841 counting only the distinct ones).

The product of its digits is 184320, while the sum is 42.

The square root of 28256388 is about 5315.6738048906. The cubic root of 28256388 is about 304.5829218111.

The spelling of 28256388 in words is "twenty-eight million, two hundred fifty-six thousand, three hundred eighty-eight".