200 (number)

200 (two hundred) is the natural number after 199 and before 201.

It is the smallest unprimeable number because changing only one of the digits will still result in a composite number.

 If we change the first digit to any other digit, we get numbers like 100, 300, 400, and so on. None of these are prime numbers.
 If we change the second digit to any other digit, we get numbers like 210, 220, 230, and so on. None of these are prime numbers.
 If we change the third digit to any other digit, we get numbers like 201, 202, 203, 204, 205, 206, 207, 208, and 209. Yet again, none of these are prime numbers.
 203 and 209 are not prime because both numbers can be expressed as the product of 7 x 29 and 11 x 19 respectively.

Category:Integers