Multiple choice general knowledge math & puzzles The square root of 64009 is: 254 251 253 252 Reveal answer Fill a bubble to check yourself C Correct answer Explanation To find the square root of 64009, note that 250^2 = 62500 and 260^2 = 67600. Since the last digit is 9, the root must end in 3 or 7. Testing 253: 253 * 253 = 64009.