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Composite Number

642

642 is a even composite number that follows 641 and precedes 643. It is composed of 8 distinct factors: 1, 2, 3, 6, 107, 214, 321, 642. Its prime factorization can be written as 2 × 3 × 107. 642 is classified as a abundant number based on the sum of its proper divisors. In computer science, 642 is represented as 1010000010 in binary and 282 in hexadecimal. Historically, it is written as DCXLII in Roman numerals.

Roman Numeral
DCXLII
LatinClassic
Binary
1010000010
Base 2
Hexadecimal
282
Base 16

Factor Analysis

8 Factors

Properties

ParityEven
Perfect SquareNo
Perfect CubeNo
Digit Count3
Digit Sum12
Digital Root3
Sum of Factors1296
Aliquot Sum654
ClassificationAbundant
Prime Factors3
SequencesComposite numbers, Abundant numbers
Prime Factorization

The prime factorization (2 × 3 × 107) reveals 3 prime building blocks.

Canonical form
2 × 3 × 107
23107
Divisibility Insights
  • Divisible by 2

    642 ends in 2, so it is even.

  • Divisible by 3

    The digit sum 12 is a multiple of 3.

  • Divisible by 4

    The last two digits 42 are not divisible by 4.

  • Divisible by 5

    642 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 12 is not a multiple of 9.

  • Divisible by 10

    642 does not end in 0.

  • Divisible by 11

    The alternating digit sum 4 is not a multiple of 11.

Sequence Membership

Abundant classification and digit analytics place 642 within several notable number theory sequences:

Composite numbersAbundant numbers
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Deep dive

How 642 breaks down

642 carries 8 distinct factors and a digit signature of 12 (3 as the digital root). The abundant classification indicates that its proper divisors sum to 654, which exceeds the number, offering a quick glimpse into its abundance profile.

Numeral conversions provide additional context: the binary form 1010000010 supports bitwise reasoning, hexadecimal 282 aligns with computing notation, and the Roman numeral DCXLII keeps the encyclopedic tradition alive. These attributes make 642 useful for math olympiad problems, puzzle design, and code challenges alike.

Context

Where 642 shows up

Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (637647) to tune search ranges, and educators feature 642 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 642 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 642

Is 642 a prime number?

642 is composite with 8 total factors and the prime factorization 2 × 3 × 107.

What is the prime factorization of 642?

It breaks down as 2 × 3 × 107, multiplying the primes 2 × 3 × 107.

How is 642 represented in binary and hexadecimal?

642 converts to 1010000010 in binary and 282 in hexadecimal, which are helpful for computer science applications.

Is 642 a perfect square, cube, or triangular number?

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

What are the digit sum and digital root of 642?

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