Multiple choice general knowledge The odd one is.. 37 47 57 67 Reveal answer Fill a bubble to check yourself C Correct answer Explanation Among these numbers, 57 is the only one that is not a prime number. 37, 47, and 67 are all prime numbers (divisible only by 1 and themselves), while 57 equals 3 × 19, making it a composite number. This makes 57 the odd one out mathematically.