28880728 has 32 divisors (see below), whose sum is σ = 55883520. Its totient is φ = 13984000.

The previous prime is 28880699. The next prime is 28880729. The reversal of 28880728 is 82708882.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28880729) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62418 + ... + 62878.

It is an arithmetic number, because the mean of its divisors is an integer number (1746360).

Almost surely, 2^28880728 is an apocalyptic number.

It is an amenable number.

28880728 is a deficient number, since it is larger than the sum of its proper divisors (27002792).

28880728 is a wasteful number, since it uses less digits than its factorization.

28880728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 699 (or 695 counting only the distinct ones).

The product of its (nonzero) digits is 114688, while the sum is 43.

The square root of 28880728 is about 5374.0792699773. The cubic root of 28880728 is about 306.8099068289.

The spelling of 28880728 in words is "twenty-eight million, eight hundred eighty thousand, seven hundred twenty-eight".