XV (Fifteen) is a numeral that represents the number 15 in the Roman numeral system. It is formed by combining the symbols X for 10 and V for 5. This system was widely used in ancient Rome and is still seen today in various contexts, such as clock faces and book chapters. In mathematics, XV is an integer that follows XIV (14) and precedes XVI (16). It is an odd number and can be expressed as the sum of three consecutive integers: 4 + 5 + 6. The number 15 also has significance in various cultures, often representing milestones or important events.