220 (number)

The number 220 is a number that comes after 219 and before 221.

 In mathematics 

 220 is an even number.
 It is a composite number, because it has more than two factors.
 The prime factorization of 220 is:   220 = 2 × 2 × 5 × 11 = 2² × 5 × 11
 The digits of 220 add up to 4 (2 + 2 + 0 = 4).

 Special property 

 220 is a friendly number!   It forms an amicable pair with 284.   The sum of the proper divisors of 220 (excluding itself) is 284, and the sum of the proper divisors of 284 is 220.

 In other areas 

 Year 220 AD marked the end of the Han Dynasty in ancient China.
 In many countries, 220 volts is a common voltage for household electricity.

Category:Integers