Seven

Seven is a natural number following six and preceding eight. It is a prime number, and is often considered lucky in various cultures and religions.

Etymology

The word "seven" comes from the Old English word "seofon," which is derived from the Proto-Germanic "sebun." Similar words for seven are found in other Germanic languages, such as "sieben" in German, "zeven" in Dutch, and "sju" in Swedish.

Mathematics

In mathematics, seven is the fourth prime number. It is not only a Mersenne prime (since 2^3 − 1 = 7) but also a double Mersenne prime as it is itself the exponent for another Mersenne Prime (2^7 − 1 = 127). Seven is the first integer reciprocal with infinitely repeating sexagesimal representation.

Symbolism

Seven is a significant number in various religions and cultures. In Judaism, there are seven days of Creation, and the Menorah has seven branches. In Christianity, God rested on the seventh day, and seven virtues and seven sins are often mentioned. In Islam, there are seven heavens and seven layers of the Earth. In Chinese culture, there are seven emotions: joy, anger, anxiety, adoration, grief, fear, and hate.

In popular culture

The number seven is often used in literature, film, music, and other forms of media. Examples include the Seven Wonders of the Ancient World, the Seven Dwarfs in Snow White, and the seven books in the Harry Potter series.

See also

• Number theory
• Numerology
• Cultural depictions of the number seven