28223500 has 48 divisors (see below), whose sum is σ = 63004032. Its totient is φ = 11040000.

The previous prime is 28223477. The next prime is 28223509. The reversal of 28223500 is 532282.

It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (28223509) 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 15 ways as a sum of consecutive naturals, for example, 22900 + ... + 24100.

It is an arithmetic number, because the mean of its divisors is an integer number (1312584).

Almost surely, 2^28223500 is an apocalyptic number.

28223500 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 28223500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31502016).

28223500 is an abundant number, since it is smaller than the sum of its proper divisors (34780532).

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

28223500 is a wasteful number, since it uses less digits than its factorization.

28223500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1267 (or 1255 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 28223500 is about 5312.5794111712. The cubic root of 28223500 is about 304.4647065129.

Adding to 28223500 its reverse (532282), we get a palindrome (28755782).

The spelling of 28223500 in words is "twenty-eight million, two hundred twenty-three thousand, five hundred".