28120928 has 24 divisors (see below), whose sum is σ = 60396840. Its totient is φ = 12782080.

The previous prime is 28120921. The next prime is 28120933. The reversal of 28120928 is 82902182.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 28120894 and 28120903.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28120921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39593 + ... + 40296.

It is an arithmetic number, because the mean of its divisors is an integer number (2516535).

Almost surely, 2^28120928 is an apocalyptic number.

It is an amenable number.

28120928 is an abundant number, since it is smaller than the sum of its proper divisors (32275912).

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

28120928 is a wasteful number, since it uses less digits than its factorization.

28120928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79910 (or 79902 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 28120928 is about 5302.9169331605. The cubic root of 28120928 is about 304.0954224916.

The spelling of 28120928 in words is "twenty-eight million, one hundred twenty thousand, nine hundred twenty-eight".