Multiple choice general knowledge math & puzzles Product of 666,666,666 Multiplied by 666,666 554443889555556 444443999444556 444443999555556 444333999333556 Reveal answer Fill a bubble to check yourself C Correct answer Explanation Multiplying 666,666,666 by 666,666 results in 444,443,999,555,556. This can be verified by long multiplication or observing the pattern of digits produced by repeating numbers in such products.