28565000 has 80 divisors (see below), whose sum is σ = 69587100. Its totient is φ = 10976000.

The previous prime is 28564979. The next prime is 28565003. The reversal of 28565000 is 56582.

It can be written as a sum of positive squares in 10 ways, for example, as 70756 + 28494244 = 266^2 + 5338^2 .

It is not an unprimeable number, because it can be changed into a prime (28565003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 144902 + ... + 145098.

Almost surely, 2^28565000 is an apocalyptic number.

28565000 is a gapful number since it is divisible by the number (20) 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 28565000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34793550).

28565000 is an abundant number, since it is smaller than the sum of its proper divisors (41022100).

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

28565000 is a wasteful number, since it uses less digits than its factorization.

28565000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252 (or 233 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 28565000 is about 5344.6234666251. The cubic root of 28565000 is about 305.6877787099.

The spelling of 28565000 in words is "twenty-eight million, five hundred sixty-five thousand".