409

409 is a natural number that follows 408 and precedes 410. It is a prime number and can be expressed as the sum of two squares: 409 = 20^2 + 3^2.

In computing and networking, 409 is the HTTP status code Conflict, returned when a request could not be completed due to a conflict with the current state of the resource.

In transportation and automotive history, Chevrolet produced a 409 cubic inch V8 engine in the early 1960s, renowned for its high performance and association with mid-century muscle cars. The engine is also celebrated in popular culture by the Beach Boys’ 1962 song “409,” which extolled its speed and power.

In materials science, 409 stainless steel is a ferritic chromium stainless steel widely used in automotive exhaust systems and decorative trim because of its corrosion resistance and formability.

Geographically, area code 409 serves parts of Southeastern Texas along the Gulf Coast, including several major coastal communities.

Historically, the number also denotes the year 409 CE in the Julian calendar, a point in late antiquity often discussed in studies of the Roman Empire and neighboring regions.