28039968 has 144 divisors (see below), whose sum is σ = 89159616. Its totient is φ = 8286720.

The previous prime is 28039961. The next prime is 28039981. The reversal of 28039968 is 86993082.

It is a tau number, because it is divible by the number of its divisors (144).

It is not an unprimeable number, because it can be changed into a prime (28039961) 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 23 ways as a sum of consecutive naturals, for example, 167821 + ... + 167987.

It is an arithmetic number, because the mean of its divisors is an integer number (619164).

Almost surely, 2^28039968 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28039968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44579808).

28039968 is an abundant number, since it is smaller than the sum of its proper divisors (61119648).

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

28039968 is a wasteful number, since it uses less digits than its factorization.

28039968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247 (or 236 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 28039968 is about 5295.2778963903. The cubic root of 28039968 is about 303.8033122905.

The spelling of 28039968 in words is "twenty-eight million, thirty-nine thousand, nine hundred sixty-eight".