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Composite Number

39

39 is a odd composite number that follows 38 and precedes 40. It is composed of 4 distinct factors: 1, 3, 13, 39. Its prime factorization can be written as 3 × 13. 39 is classified as a deficient number based on the sum of its proper divisors. In computer science, 39 is represented as 100111 in binary and 27 in hexadecimal. Historically, it is written as XXXIX in Roman numerals.

Roman Numeral
XXXIX
LatinClassic
Binary
100111
Base 2
Hexadecimal
27
Base 16

Factor Analysis

4 Factors

Properties

ParityOdd
Perfect SquareNo
Perfect CubeNo
Digit Count2
Digit Sum12
Digital Root3
Sum of Factors56
Aliquot Sum17
ClassificationDeficient
Prime Factors2
SequencesComposite numbers, Deficient numbers
Prime Factorization

The prime factorization (3 × 13) reveals 2 prime building blocks.

Canonical form
3 × 13
313
Divisibility Insights
  • Divisible by 2

    39 ends in 9, so it is odd.

  • Divisible by 3

    The digit sum 12 is a multiple of 3.

  • Divisible by 4

    The last two digits 39 are not divisible by 4.

  • Divisible by 5

    39 does not end in 0 or 5.

  • Divisible by 6

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

  • Divisible by 9

    The digit sum 12 is not a multiple of 9.

  • Divisible by 10

    39 does not end in 0.

  • Divisible by 11

    The alternating digit sum -6 is not a multiple of 11.

Sequence Membership

Deficient classification and digit analytics place 39 within several notable number theory sequences:

Composite numbersDeficient numbers
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Deep dive

How 39 breaks down

39 carries 4 distinct factors and a digit signature of 12 (3 as the digital root). The deficient classification indicates that its proper divisors sum to 17, which stays below the number, offering a quick glimpse into its abundance profile.

Numeral conversions provide additional context: the binary form 100111 supports bitwise reasoning, hexadecimal 27 aligns with computing notation, and the Roman numeral XXXIX keeps the encyclopedic tradition alive. These attributes make 39 useful for math olympiad problems, puzzle design, and code challenges alike.

Context

Where 39 shows up

Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (3444) to tune search ranges, and educators feature 39 in worksheets about factor trees. Its binary footprint of length 6 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 39 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 39

Is 39 a prime number?

39 is composite with 4 total factors and the prime factorization 3 × 13.

What is the prime factorization of 39?

It breaks down as 3 × 13, multiplying the primes 3 × 13.

How is 39 represented in binary and hexadecimal?

39 converts to 100111 in binary and 27 in hexadecimal, which are helpful for computer science applications.

Is 39 a perfect square, cube, or triangular number?

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

What are the digit sum and digital root of 39?

The digits sum to 12, producing a digital root of 3. These tests power divisibility shortcuts for 3 and 9.