28689888 has 24 divisors (see below), whose sum is σ = 75311208. Its totient is φ = 9563264.

The previous prime is 28689851. The next prime is 28689889. The reversal of 28689888 is 88898682.

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28689889) 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, 149331 + ... + 149522.

It is an arithmetic number, because the mean of its divisors is an integer number (3137967).

Almost surely, 2^28689888 is an apocalyptic number.

It is an amenable number.

28689888 is an abundant number, since it is smaller than the sum of its proper divisors (46621320).

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

28689888 is a wasteful number, since it uses less digits than its factorization.

28689888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 298866 (or 298858 counting only the distinct ones).

The product of its digits is 3538944, while the sum is 57.

The square root of 28689888 is about 5356.2942413575. The cubic root of 28689888 is about 306.1326265191.

The spelling of 28689888 in words is "twenty-eight million, six hundred eighty-nine thousand, eight hundred eighty-eight".