Special numbers are unique numbers that have distinct properties or significance in mathematics. Examples include prime numbers, which are greater than 1 and can only be divided by 1 and themselves, and perfect numbers, which are equal to the sum of their proper divisors. Another category is Fibonacci numbers, a sequence where each number is the sum of the two preceding ones, starting from 0 and 1. Special numbers often appear in various fields, including geometry, number theory, and even in nature, such as the golden ratio, which is approximately 1.618 and is often found in art and architecture.