28218 has 8 divisors (see below), whose sum is σ = 56448. Its totient is φ = 9404.

The previous prime is 28211. The next prime is 28219. The reversal of 28218 is 81282.

It is a sphenic number, since it is the product of 3 distinct primes.

28218 is an admirable number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28194 and 28203.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 28218.

It is not an unprimeable number, because it can be changed into a prime (28211) by changing a digit.

28218 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2346 + ... + 2357.

It is an arithmetic number, because the mean of its divisors is an integer number (7056).

2²⁸²¹⁸ is an apocalyptic number.

28218 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28224).

28218 is a wasteful number, since it uses less digits than its factorization.

28218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4708.

The product of its digits is 256, while the sum is 21.

The square root of 28218 is about 167.9821419080. The cubic root of 28218 is about 30.4444927904. Note that the first 4 decimals are identical.

It can be divided in two parts, 282 and 18, that added together give a triangular number (300 = T₂₄).

The spelling of 28218 in words is "twenty-eight thousand, two hundred eighteen".