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Composite Number

1145

1145 is a odd composite number that follows 1144 and precedes 1146. It is composed of 4 distinct factors: 1, 5, 229, 1145. Its prime factorization can be written as 5 × 229. 1145 is classified as a deficient number based on the sum of its proper divisors. In computer science, 1145 is represented as 10001111001 in binary and 479 in hexadecimal. Historically, it is written as MCXLV in Roman numerals.

Roman Numeral
MCXLV
LatinClassic
Binary
10001111001
Base 2
Hexadecimal
479
Base 16

Factor Analysis

4 Factors

Properties

ParityOdd
Perfect SquareNo
Perfect CubeNo
Digit Count4
Digit Sum11
Digital Root2
Sum of Factors1380
Aliquot Sum235
ClassificationDeficient
Prime Factors2
SequencesComposite numbers, Deficient numbers
Prime Factorization

The prime factorization (5 × 229) reveals 2 prime building blocks.

Canonical form
5 × 229
5229
Divisibility Insights
  • Divisible by 2

    1145 ends in 5, so it is odd.

  • Divisible by 3

    The digit sum 11 is not a multiple of 3.

  • Divisible by 4

    The last two digits 45 are not divisible by 4.

  • Divisible by 5

    1145 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 11 is not a multiple of 9.

  • Divisible by 10

    1145 does not end in 0.

  • Divisible by 11

    The alternating digit sum -1 is not a multiple of 11.

Sequence Membership

Deficient classification and digit analytics place 1145 within several notable number theory sequences:

Composite numbersDeficient numbers
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Deep dive

How 1145 breaks down

1145 carries 4 distinct factors and a digit signature of 11 (2 as the digital root). The deficient classification indicates that its proper divisors sum to 235, which stays below the number, offering a quick glimpse into its abundance profile.

Numeral conversions provide additional context: the binary form 10001111001 supports bitwise reasoning, hexadecimal 479 aligns with computing notation, and the Roman numeral MCXLV keeps the encyclopedic tradition alive. These attributes make 1145 useful for math olympiad problems, puzzle design, and code challenges alike.

Context

Where 1145 shows up

Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (11401150) to tune search ranges, and educators feature 1145 in worksheets about factor trees. Its binary footprint of length 11 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 1145 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 1145

Is 1145 a prime number?

1145 is composite with 4 total factors and the prime factorization 5 × 229.

What is the prime factorization of 1145?

It breaks down as 5 × 229, multiplying the primes 5 × 229.

How is 1145 represented in binary and hexadecimal?

1145 converts to 10001111001 in binary and 479 in hexadecimal, which are helpful for computer science applications.

Is 1145 a perfect square, cube, or triangular number?

1145 is not a perfect square, is not a perfect cube, and is not triangular.

What are the digit sum and digital root of 1145?

The digits sum to 11, producing a digital root of 2. These tests power divisibility shortcuts for 3 and 9.