Is 336 a perfect square ? If not, find the smallest number by which 336 be multiplied so that the resulting number is a perfect square.

Finding prime factors of 336

$336 = (2 \times 2) \times (2 \times 2) \times 3 \times 7$

Since the prime factor 3 and 7 are not in pair. So we need one more 3 and one more 7 : 3 × 7 = 21.

Hence, 336 is not a perfect square and 21 is the smallest number that should be multiplied with 336 so that the product is a perfect square.