5 Letter Words That Start With U: The Words That Will Help You Win Any Argument. - Fizz News

5 . 5 (five) is a number, numeral and digit. It is the natural number, and cardinal number, following 4 and preceding 6, and is a prime number. Humans, and many other animals, have 5 digits on their limbs. Your guide to the number 5, an odd number which is prime. Mathematical info, prime factorization, fun facts and numerical data for STEM, education and fun.