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Composite Number

42

42 is a even composite number that follows 41 and precedes 43. It is composed of 8 distinct factors: 1, 2, 3, 6, 7, 14, 21, 42. Its prime factorization can be written as 2 × 3 × 7. 42 is classified as a abundant number based on the sum of its proper divisors. In computer science, 42 is represented as 101010 in binary and 2A in hexadecimal. Historically, it is written as XLII in Roman numerals.

Roman Numeral
XLII
LatinClassic
Binary
101010
Base 2
Hexadecimal
2A
Base 16

Factor Analysis

8 Factors

Properties

ParityEven
Perfect SquareNo
Perfect CubeNo
Digit Count2
Digit Sum6
Digital Root6
Sum of Factors96
Aliquot Sum54
ClassificationAbundant
Prime Factors3
SequencesComposite numbers, Abundant numbers
Prime Factorization

The prime factorization (2 × 3 × 7) reveals 3 prime building blocks.

Canonical form
2 × 3 × 7
237
Divisibility Insights
  • Divisible by 2

    42 ends in 2, so it is even.

  • Divisible by 3

    The digit sum 6 is a multiple of 3.

  • Divisible by 4

    The last two digits 42 are not divisible by 4.

  • Divisible by 5

    42 does not end in 0 or 5.

  • Divisible by 6

    It meets the tests for both 2 and 3, so it is divisible by 6.

  • Divisible by 9

    The digit sum 6 is not a multiple of 9.

  • Divisible by 10

    42 does not end in 0.

  • Divisible by 11

    The alternating digit sum 2 is not a multiple of 11.

Sequence Membership

Abundant classification and digit analytics place 42 within several notable number theory sequences:

Composite numbersAbundant numbers
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Deep dive

How 42 breaks down

42 carries 8 distinct factors and a digit signature of 6 (6 as the digital root). The abundant classification indicates that its proper divisors sum to 54, which exceeds the number, offering a quick glimpse into its abundance profile.

Numeral conversions provide additional context: the binary form 101010 supports bitwise reasoning, hexadecimal 2A aligns with computing notation, and the Roman numeral XLII keeps the encyclopedic tradition alive. These attributes make 42 useful for math olympiad problems, puzzle design, and code challenges alike.

Context

Where 42 shows up

Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (3747) to tune search ranges, and educators feature 42 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, Abundant numbers) help historians, numerologists, and trivia writers tie 42 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 42

Is 42 a prime number?

42 is composite with 8 total factors and the prime factorization 2 × 3 × 7.

What is the prime factorization of 42?

It breaks down as 2 × 3 × 7, multiplying the primes 2 × 3 × 7.

How is 42 represented in binary and hexadecimal?

42 converts to 101010 in binary and 2A in hexadecimal, which are helpful for computer science applications.

Is 42 a perfect square, cube, or triangular number?

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

What are the digit sum and digital root of 42?

The digits sum to 6, producing a digital root of 6. These tests power divisibility shortcuts for 3 and 9.