9 is the fourth composite number, and the first odd composite number. 9 is also a refactorable number. [2] Casting out nines is a quick way of testing the calculations of sums, differences, products, and quotients of integers in decimal, a method known as long ago as the 12th century. [3] 9 is the only square number that is the sum of two consecutive, positive cubes: [4] If an odd perfect ...
Your guide to the number 9, an odd composite number composed of a single prime multiplied by itself. Mathematical info, prime factorization, fun facts and numerical data for STEM, education and fun.
九 (gau2, “nine”) and 鳩 / 鸠 (gau1) are near homophones in Cantonese.
The number 9 is incredibly prevalent in the world around us and can be found in many areas. Here are ten incredible facts about the number 9.