The number 7 is a prime number and a Mersenne prime.
The prefixes "sept" and "hept" both mean "seven".
There are seven Deadly Sins in Christian teachings.
There are seven continents, depending on where you're from.
A US park ranger was struck by lightning seven times and survived.
Musicians have a fascination with the number seven.
In some parts of the world, cats have seven lives, not nine.
The average person can accurately remember a series of seven digits.
A rainbow contains seven clearly defined colors.
The seventh son of a seventh son holds special powers in folklore.
From prime numbers to musical obsessions, the number seven is truly superb.