28878255 has 32 divisors (see below), whose sum is σ = 58675200. Its totient is φ = 13201056.

The previous prime is 28878251. The next prime is 28878281. The reversal of 28878255 is 55287882.

It is not a de Polignac number, because 28878255 - 2² = 28878251 is a prime.

It is a super-2 number, since 2×28878255² = 1667907223690050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 28878255.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28878251) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14335 + ... + 16224.

It is an arithmetic number, because the mean of its divisors is an integer number (1833600).

Almost surely, 2^28878255 is an apocalyptic number.

28878255 is an abundant number, since it is smaller than the sum of its proper divisors (29796945).

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

28878255 is a wasteful number, since it uses less digits than its factorization.

28878255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30580 (or 30574 counting only the distinct ones).

The product of its digits is 358400, while the sum is 45.

The square root of 28878255 is about 5373.8491791266. The cubic root of 28878255 is about 306.8011494024.

The spelling of 28878255 in words is "twenty-eight million, eight hundred seventy-eight thousand, two hundred fifty-five".