If the greatest common factor of two numbers is 1 and their least common multiple is 18, what is the smallest sum of these two numbers?
如果两个数的最大公因数是1，他们的最小公倍数是18，那么这两个数的和最小是多少．
<gadget id="calculator">2 + 9</gadget>
<output>11</output>

<result>11</result>