The number thirty-three is an integer that follows thirty-two and precedes thirty-four. It is often represented in Roman numerals as XXXIII. In mathematics, thirty-three is classified as a composite number, meaning it has divisors other than one and itself, specifically 1, 3, 11, and 33. In various cultures, the number thirty-three holds significance. For example, in Freemasonry, it is considered a master number, representing a high degree of knowledge and enlightenment. Additionally, there are thirty-three vertebrae in the human spine, which contributes to its importance in anatomy and health discussions.