28222218 has 12 divisors (see below), whose sum is σ = 61148178. Its totient is φ = 9407400.

The previous prime is 28222217. The next prime is 28222223. The reversal of 28222218 is 81222282.

It can be written as a sum of positive squares in only one way, i.e., 22155849 + 6066369 = 4707^2 + 2463^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28222191 and 28222200.

It is not an unprimeable number, because it can be changed into a prime (28222217) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 783933 + ... + 783968.

Almost surely, 2^28222218 is an apocalyptic number.

28222218 is an abundant number, since it is smaller than the sum of its proper divisors (32925960).

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

28222218 is a wasteful number, since it uses less digits than its factorization.

28222218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1567909 (or 1567906 counting only the distinct ones).

The product of its digits is 2048, while the sum is 27.

The square root of 28222218 is about 5312.4587527811. The cubic root of 28222218 is about 304.4600965287.

It can be divided in two parts, 282 and 22218, that added together give a square (22500 = 150²).

The spelling of 28222218 in words is "twenty-eight million, two hundred twenty-two thousand, two hundred eighteen".