28221200 has 60 divisors (see below), whose sum is σ = 77495040. Its totient is φ = 9674880.

The previous prime is 28221181. The next prime is 28221209. The reversal of 28221200 is 212282.

It is a super-2 number, since 2×28221200² = 1592872258880000, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28221209) 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 11 ways as a sum of consecutive naturals, for example, 2240 + ... + 7839.

It is an arithmetic number, because the mean of its divisors is an integer number (1291584).

Almost surely, 2^28221200 is an apocalyptic number.

28221200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28221200 is an abundant number, since it is smaller than the sum of its proper divisors (49273840).

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

28221200 is a wasteful number, since it uses less digits than its factorization.

28221200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10104 (or 10093 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 28221200 is about 5312.3629394084. The cubic root of 28221200 is about 304.4564357711.

Adding to 28221200 its reverse (212282), we get a palindrome (28433482).

The spelling of 28221200 in words is "twenty-eight million, two hundred twenty-one thousand, two hundred".