28804240 has 20 divisors (see below), whose sum is σ = 66970044. Its totient is φ = 11521664.

The previous prime is 28804229. The next prime is 28804249. The reversal of 28804240 is 4240882.

It can be written as a sum of positive squares in 2 ways, for example, as 16777216 + 12027024 = 4096^2 + 3468^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 28804199 and 28804208.

It is not an unprimeable number, because it can be changed into a prime (28804249) by changing a digit.

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, 179947 + ... + 180106.

Almost surely, 2^28804240 is an apocalyptic number.

28804240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28804240 is an abundant number, since it is smaller than the sum of its proper divisors (38165804).

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

28804240 is a wasteful number, since it uses less digits than its factorization.

28804240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360066 (or 360060 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 28.

The square root of 28804240 is about 5366.9581701370. The cubic root of 28804240 is about 306.5388145896.

The spelling of 28804240 in words is "twenty-eight million, eight hundred four thousand, two hundred forty".