28521664 has 28 divisors (see below), whose sum is σ = 56767984. Its totient is φ = 14217984.

The previous prime is 28521659. The next prime is 28521673. The reversal of 28521664 is 46612582.

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, 38869 + ... + 39595.

It is an arithmetic number, because the mean of its divisors is an integer number (2027428).

Almost surely, 2^28521664 is an apocalyptic number.

It is an amenable number.

28521664 is a deficient number, since it is larger than the sum of its proper divisors (28246320).

28521664 is an equidigital number, since it uses as much as digits as its factorization.

28521664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1352 (or 1342 counting only the distinct ones).

The product of its digits is 23040, while the sum is 34.

The square root of 28521664 is about 5340.5677600794. The cubic root of 28521664 is about 305.5331140225.

The spelling of 28521664 in words is "twenty-eight million, five hundred twenty-one thousand, six hundred sixty-four".