The number "90" is an integer that follows 89 and precedes 91. It is an even number and can be divided by 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, and 45, making it a composite number. In Roman numerals, 90 is represented as XC. In terms of angles, 90 degrees is significant as it represents a right angle, commonly found in geometry. This angle is essential in various fields, including architecture and engineering, as it helps create perpendicular lines and structures. Additionally, 90 is often used in sports to denote a score or performance metric.