745

745 is the natural number that follows 744 and precedes 746. In mathematics, it is an odd composite number with prime factorization 5 × 149; its positive divisors are 1, 5, 149, and 745. The sum of its digits is 16, so it is not divisible by 3 or 9, and it is divisible by 5. In modular arithmetic, 745 is congruent to 1 modulo 3, 4, and 8.

Representations in different numeral systems include binary, octal, hexadecimal, and Roman numerals. In binary it is 1011101001, in octal 1351, and in hexadecimal 2E9. In Roman numerals it is DCCXLV. It lies between 2^9 and 2^10, placing its value around 7.45 × 10^2.

As a year, 745 CE is in the early medieval period. It is used in historical chronology and terminology to reference events, developments, and contexts across various regions of the world during the eighth century. Specific interpretations and notable happenings surrounding this year vary by source and region, and scholars place events within the broader patterns of the era rather than a single defining moment for the year itself.

In broader usage, 745 may appear in identifiers, catalog numbers, or designations across different domains, but as a standalone number it is primarily recognized for its numerical properties and its place in calendar-era notation.