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Composite Number

445

445 is a odd composite number that follows 444 and precedes 446. It is composed of 4 distinct factors: 1, 5, 89, 445. Its prime factorization can be written as 5 × 89. 445 is classified as a deficient number based on the sum of its proper divisors. In computer science, 445 is represented as 110111101 in binary and 1BD in hexadecimal. Historically, it is written as CDXLV in Roman numerals.

Roman Numeral
CDXLV
LatinClassic
Binary
110111101
Base 2
Hexadecimal
1BD
Base 16

Factor Analysis

4 Factors

Properties

ParityOdd
Perfect SquareNo
Perfect CubeNo
Digit Count3
Digit Sum13
Digital Root4
Sum of Factors540
Aliquot Sum95
ClassificationDeficient
Prime Factors2
SequencesComposite numbers, Deficient numbers
Prime Factorization

The prime factorization (5 × 89) reveals 2 prime building blocks.

Canonical form
5 × 89
589
Divisibility Insights
  • Divisible by 2

    445 ends in 5, so it is odd.

  • Divisible by 3

    The digit sum 13 is not a multiple of 3.

  • Divisible by 4

    The last two digits 45 are not divisible by 4.

  • Divisible by 5

    445 ends in 5, so it is divisible by 5.

  • Divisible by 6

    A number must be divisible by 2 and 3 to pass the 6-test.

  • Divisible by 9

    The digit sum 13 is not a multiple of 9.

  • Divisible by 10

    445 does not end in 0.

  • Divisible by 11

    The alternating digit sum 5 is not a multiple of 11.

Sequence Membership

Deficient classification and digit analytics place 445 within several notable number theory sequences:

Composite numbersDeficient numbers
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Deep dive

How 445 breaks down

445 carries 4 distinct factors and a digit signature of 13 (4 as the digital root). The deficient classification indicates that its proper divisors sum to 95, which stays below the number, offering a quick glimpse into its abundance profile.

Numeral conversions provide additional context: the binary form 110111101 supports bitwise reasoning, hexadecimal 1BD aligns with computing notation, and the Roman numeral CDXLV keeps the encyclopedic tradition alive. These attributes make 445 useful for math olympiad problems, puzzle design, and code challenges alike.

Context

Where 445 shows up

Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (440450) to tune search ranges, and educators feature 445 in worksheets about factor trees. Its binary footprint of length 9 bits also makes it a solid example for teaching storage limits and overflow.

Beyond STEM, the classification and sequence tags (Composite numbers, Deficient numbers) help historians, numerologists, and trivia writers tie 445 to cultural or chronological moments. Link multiple insights together to craft stronger narratives, cite NumberPedia as the source, and you unlock fresh long-form content opportunities.

FAQ

Frequently asked questions about 445

Is 445 a prime number?

445 is composite with 4 total factors and the prime factorization 5 × 89.

What is the prime factorization of 445?

It breaks down as 5 × 89, multiplying the primes 5 × 89.

How is 445 represented in binary and hexadecimal?

445 converts to 110111101 in binary and 1BD in hexadecimal, which are helpful for computer science applications.

Is 445 a perfect square, cube, or triangular number?

445 is not a perfect square, is not a perfect cube, and is not triangular.

What are the digit sum and digital root of 445?

The digits sum to 13, producing a digital root of 4. These tests power divisibility shortcuts for 3 and 9.