28091688 has 16 divisors (see below), whose sum is σ = 70229280. Its totient is φ = 9363888.

The previous prime is 28091677. The next prime is 28091711. The reversal of 28091688 is 88619082.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 585220 + ... + 585267.

It is an arithmetic number, because the mean of its divisors is an integer number (4389330).

Almost surely, 2^28091688 is an apocalyptic number.

It is an amenable number.

28091688 is an abundant number, since it is smaller than the sum of its proper divisors (42137592).

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

28091688 is a wasteful number, since it uses less digits than its factorization.

28091688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1170496 (or 1170492 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 42.

The square root of 28091688 is about 5300.1592428907. The cubic root of 28091688 is about 303.9899869740.

The spelling of 28091688 in words is "twenty-eight million, ninety-one thousand, six hundred eighty-eight".