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. 5 is a Fermat prime, a Mersenne prime exponent, [1] as well as a Fibonacci number. 5 is the first congruent number, as well as the length of the hypotenuse of the smallest integer-sided right triangle, making part of the smallest Pythagorean triple (3, 4, 5 ). Learn the different ways number 5 can be represented. See the number five on a number line, five frame, ten frame, numeral, word, dice, dominoes, tally mark, fingers and picture representations. Mathematics Five is the third prime number, after two and three, and before seven. The number five is also an odd number. Most people have five fingers (including one thumb) on each hand and five toes on each foot. Numbers ending in five are always divisible by 5 The number 5 exists
