28508928 has 72 divisors (see below), whose sum is σ = 86731008. Its totient is φ = 8143872.

The previous prime is 28508903. The next prime is 28508947. The reversal of 28508928 is 82980582.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 28508928.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2725 + ... + 8027.

Almost surely, 2^28508928 is an apocalyptic number.

28508928 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28508928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43365504).

28508928 is an abundant number, since it is smaller than the sum of its proper divisors (58222080).

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

28508928 is an equidigital number, since it uses as much as digits as its factorization.

28508928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5329 (or 5315 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 42.

The square root of 28508928 is about 5339.3752443521. The cubic root of 28508928 is about 305.4876298941.

The spelling of 28508928 in words is "twenty-eight million, five hundred eight thousand, nine hundred twenty-eight".