Natural numbersSquare numbersCategories requiring diffusion Help Category:9 (number) From Wikimedia Commons, the free media repository Jump to navigation Jump to search number: 9 (nine) instance of: natural number, deficient number, square number, composite number, odd number, centered cube number, centered octagonal number and nonagonal number other integers: -8 • -4 • -2 • -1 • 0 • 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 • 26 • 27 • 28 • 29 -20 • 0 • 10 • 20 • 30 ...