28686688 has 24 divisors (see below), whose sum is σ = 56600208. Its totient is φ = 14312064.

The previous prime is 28686677. The next prime is 28686689. The reversal of 28686688 is 88668682.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28686689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22845 + ... + 24067.

It is an arithmetic number, because the mean of its divisors is an integer number (2358342).

Almost surely, 2^28686688 is an apocalyptic number.

It is an amenable number.

28686688 is a deficient number, since it is larger than the sum of its proper divisors (27913520).

28686688 is a wasteful number, since it uses less digits than its factorization.

28686688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1966 (or 1958 counting only the distinct ones).

The product of its digits is 1769472, while the sum is 52.

The square root of 28686688 is about 5355.9955190422. The cubic root of 28686688 is about 306.1212443342.

The spelling of 28686688 in words is "twenty-eight million, six hundred eighty-six thousand, six hundred eighty-eight".