778

778 is a natural number that lies between 777 and 779. In mathematics, it is an even composite number with prime factorization 2 × 389. Its divisors are 1, 2, 389, and 778. In various numeral systems, 778 is written as 1100001010 in binary, 0x30A in hexadecimal, and 0o1412 in octal. The sum of its decimal digits is 22, and its digital root is 4. The Roman numeral representation is DCCLXXVIII.

778 is also an area code in the North American Numbering Plan for the Canadian province of British Columbia. It was introduced as an overlay for the 604 region and is used in the Vancouver metropolitan area and surrounding regions. Because of the overlay, ten-digit dialing is required in its service area.

As a calendar year, 778 CE is used in historical chronologies to refer to events in the early medieval period. In that context, it may mark occurrences across different regions, though specific events are not detailed here.