679

679 is a natural number that comes after 678 and before 680. It is used in arithmetic, counting, and cataloging as a discrete quantity.

In mathematics, 679 is a composite number, with prime factorization 7 × 97. It is a semiprime and not a square. The sum of its digits is 22, not divisible by 3, so 679 is not divisible by 3. In base representations: binary 1010100111, octal 1247, hex 2A7. In Roman numerals it is written as DCLXXIX.

Historical usage: In the Christian calendar, the year 679 CE falls in the early part of the 7th century. It occurred during the era of the Byzantine Empire and the early Islamic Caliphate, with ongoing political and military developments in the Mediterranean region.

Apart from numbers, 679 does not have a widely recognized singular meaning; it is used as an identifier in catalogues, model numbers, or numbering schemes, and as a year in historical and scholarly contexts.