The smallest number is the LCM of the first 12 natural numbers, that is, the numbers from 1 to 12. Any number which is a factor of a higher number in the list can be crossed off leaving 7, 8, 9, 10, 11, 12.
8 and 10 have an LCM of 40: 9 and 12 have an LCM of 36; 36 and 40 have an LCM of 360. So the LCM of 360, 7 and 11 is 27720, the smallest number divisible by consecutive numbers from 1 to 12.