28939904 has 32 divisors (see below), whose sum is σ = 65892000. Its totient is φ = 12402432.

The previous prime is 28939877. The next prime is 28939949. The reversal of 28939904 is 40993982.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

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, 15254 + ... + 17045.

It is an arithmetic number, because the mean of its divisors is an integer number (2059125).

Almost surely, 2^28939904 is an apocalyptic number.

It is an amenable number.

28939904 is an abundant number, since it is smaller than the sum of its proper divisors (36952096).

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

28939904 is an equidigital number, since it uses as much as digits as its factorization.

28939904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32320 (or 32308 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 44.

The square root of 28939904 is about 5379.5821399064. The cubic root of 28939904 is about 307.0193128715.

The spelling of 28939904 in words is "twenty-eight million, nine hundred thirty-nine thousand, nine hundred four".