445

445 is a natural number that follows 444 and precedes 446. It is an odd composite number with a prime factorization of 5 multiplied by 89. In base ten the sum of its digits is 13, and the number itself in binary is 110111001, in hexadecimal it is 0x1BD, and in octal it is 0665. Although 445 is not a prime or a perfect square, it is a triangular number, being the sum of the series 1 through 30 minus the sum of the series 1 through 27. It also forms a palindrome in base 14 (1A6A1).

In historical context, the year 445 CE—often written as 445 AD—was a time of continued Christian expansion in the Roman Empire and the beginning of significant migrations of Germanic tribes into Roman territories. Notable events surrounding that year include the rise of the Ostrogothic king Theodoric the Great. In cultural references, 445 is sometimes used as an arbitrary numeric designation for fictional locations or organizations, for example in science‑fiction plots or in the naming of environments in certain video games where it serves as an unused code.

The number 445 also shows up in standard telephone area codes and in postal codes in various countries; for example, area code 445 covers parts of the United Kingdom’s 0 prefix system, while postal code 445XX can denote a specific district in France. Because it is a moderately sized odd integer, 445 is occasionally referenced in puzzle and problem‑setting contexts, such as determining properties of sums of squares or representations in continued fractions.