28564224 has 72 divisors (see below), whose sum is σ = 81898992. Its totient is φ = 8785920.

The previous prime is 28564219. The next prime is 28564271. The reversal of 28564224 is 42246582.

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, 8554 + ... + 11414.

It is an arithmetic number, because the mean of its divisors is an integer number (1137486).

Almost surely, 2^28564224 is an apocalyptic number.

28564224 is a gapful number since it is divisible by the number (24) 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 28564224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40949496).

28564224 is an abundant number, since it is smaller than the sum of its proper divisors (53334768).

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

28564224 is a wasteful number, since it uses less digits than its factorization.

28564224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2893 (or 2879 counting only the distinct ones).

The product of its digits is 30720, while the sum is 33.

The square root of 28564224 is about 5344.5508698112. The cubic root of 28564224 is about 305.6850105686.

The spelling of 28564224 in words is "twenty-eight million, five hundred sixty-four thousand, two hundred twenty-four".