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Composite Number

945

945 is a odd composite number that follows 944 and precedes 946. It is composed of 16 distinct factors: 1, 3, 5, 7, 9, 15, 21, 27, 35, 45, 63, 105, 135, 189, 315, 945. Its prime factorization can be written as 3^3 × 5 × 7. 945 is classified as a abundant number based on the sum of its proper divisors. In computer science, 945 is represented as 1110110001 in binary and 3B1 in hexadecimal. Historically, it is written as CMXLV in Roman numerals.

Roman Numeral
CMXLV
LatinClassic
Binary
1110110001
Base 2
Hexadecimal
3B1
Base 16

Factor Analysis

16 Factors

Properties

ParityOdd
Perfect SquareNo
Perfect CubeNo
Digit Count3
Digit Sum18
Digital Root9
Sum of Factors1920
Aliquot Sum975
ClassificationAbundant
Prime Factors5
SequencesComposite numbers, Abundant numbers
Prime Factorization

The prime factorization (3^3 × 5 × 7) reveals 5 prime building blocks.

Canonical form
3^3 × 5 × 7
33357
Divisibility Insights
  • Divisible by 2

    945 ends in 5, so it is odd.

  • Divisible by 3

    The digit sum 18 is a multiple of 3.

  • Divisible by 4

    The last two digits 45 are not divisible by 4.

  • Divisible by 5

    945 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 18 is a multiple of 9.

  • Divisible by 10

    945 does not end in 0.

  • Divisible by 11

    The alternating digit sum 10 is not a multiple of 11.

Sequence Membership

Abundant classification and digit analytics place 945 within several notable number theory sequences:

Composite numbersAbundant numbers
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Deep dive

How 945 breaks down

945 carries 16 distinct factors and a digit signature of 18 (9 as the digital root). The abundant classification indicates that its proper divisors sum to 975, which exceeds the number, offering a quick glimpse into its abundance profile.

Numeral conversions provide additional context: the binary form 1110110001 supports bitwise reasoning, hexadecimal 3B1 aligns with computing notation, and the Roman numeral CMXLV keeps the encyclopedic tradition alive. These attributes make 945 useful for math olympiad problems, puzzle design, and code challenges alike.

Context

Where 945 shows up

Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (940950) to tune search ranges, and educators feature 945 in worksheets about factor trees. Its binary footprint of length 10 bits also makes it a solid example for teaching storage limits and overflow.

Beyond STEM, the classification and sequence tags (Composite numbers, Abundant numbers) help historians, numerologists, and trivia writers tie 945 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 945

Is 945 a prime number?

945 is composite with 16 total factors and the prime factorization 3^3 × 5 × 7.

What is the prime factorization of 945?

It breaks down as 3^3 × 5 × 7, multiplying the primes 3 × 3 × 3 × 5 × 7.

How is 945 represented in binary and hexadecimal?

945 converts to 1110110001 in binary and 3B1 in hexadecimal, which are helpful for computer science applications.

Is 945 a perfect square, cube, or triangular number?

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

What are the digit sum and digital root of 945?

The digits sum to 18, producing a digital root of 9. These tests power divisibility shortcuts for 3 and 9.