28776188 has 24 divisors (see below), whose sum is σ = 58531200. Its totient is φ = 12122928.

The previous prime is 28776157. The next prime is 28776193. The reversal of 28776188 is 88167782.

It is a happy number.

It is a super-2 number, since 2×28776188² = 1656137991622688, which contains 22 as substring.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7058 + ... + 10361.

It is an arithmetic number, because the mean of its divisors is an integer number (2438800).

Almost surely, 2^28776188 is an apocalyptic number.

28776188 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

28776188 is an abundant number, since it is smaller than the sum of its proper divisors (29755012).

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

28776188 is a wasteful number, since it uses less digits than its factorization.

28776188 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17489 (or 17487 counting only the distinct ones).

The product of its digits is 301056, while the sum is 47.

The square root of 28776188 is about 5364.3441351203. The cubic root of 28776188 is about 306.4392711448.

The spelling of 28776188 in words is "twenty-eight million, seven hundred seventy-six thousand, one hundred eighty-eight".