415

415 is a natural number that follows 414 and precedes 416. It is an odd composite number.

Its prime factorization is 5 × 83, giving divisors 1, 5, 83, and 415. In Roman numerals it is written as CDXV. In different numeral systems, 415 is 110011111 in binary, 0x19F in hexadecimal, and 0637 in octal.

In calendar usage, 4/15 denotes April 15 in month-day notation. In the United States, this date has been associated with the traditional federal income tax filing deadline, though the exact date can vary by year.

Area code 415 covers a portion of Northern California, including San Francisco and parts of Marin County. It was one of the original area codes established in 1947. Due to growing demand, an overlay area code, 628, was introduced to the same region, leading to nationwide ten-digit dialing for local calls.

In computing, HTTP status code 415 indicates Unsupported Media Type, meaning the server refuses to process a request because the payload format is not supported by the target resource. The number 415 also appears in various scientific, manufacturing, and logistical contexts as a simple numeric identifier or label.