The number "215" is an integer that follows 214 and precedes 216. It is an odd number and can be expressed as the sum of two prime numbers: 107 + 108. In mathematics, it is classified as a composite number because it has divisors other than 1 and itself. In the context of area codes, 215 is the telephone area code for parts of Pennsylvania, including the city of Philadelphia. This area code was one of the original area codes established in 1947 and is still in use today, serving a significant urban population.