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Composite Number

678

678 is a even composite number that follows 677 and precedes 679. It is composed of 8 distinct factors: 1, 2, 3, 6, 113, 226, 339, 678. Its prime factorization can be written as 2 × 3 × 113. 678 is classified as a abundant number based on the sum of its proper divisors. In computer science, 678 is represented as 1010100110 in binary and 2A6 in hexadecimal. Historically, it is written as DCLXXVIII in Roman numerals.

Roman Numeral
DCLXXVIII
LatinClassic
Binary
1010100110
Base 2
Hexadecimal
2A6
Base 16

Factor Analysis

8 Factors

Properties

ParityEven
Perfect SquareNo
Perfect CubeNo
Digit Count3
Digit Sum21
Digital Root3
Sum of Factors1368
Aliquot Sum690
ClassificationAbundant
Prime Factors3
SequencesComposite numbers, Abundant numbers
Prime Factorization

The prime factorization (2 × 3 × 113) reveals 3 prime building blocks.

Canonical form
2 × 3 × 113
23113
Divisibility Insights
  • Divisible by 2

    678 ends in 8, so it is even.

  • Divisible by 3

    The digit sum 21 is a multiple of 3.

  • Divisible by 4

    The last two digits 78 are not divisible by 4.

  • Divisible by 5

    678 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 21 is not a multiple of 9.

  • Divisible by 10

    678 does not end in 0.

  • Divisible by 11

    The alternating digit sum 7 is not a multiple of 11.

Sequence Membership

Abundant classification and digit analytics place 678 within several notable number theory sequences:

Composite numbersAbundant numbers
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Deep dive

How 678 breaks down

678 carries 8 distinct factors and a digit signature of 21 (3 as the digital root). The abundant classification indicates that its proper divisors sum to 690, which exceeds the number, offering a quick glimpse into its abundance profile.

Numeral conversions provide additional context: the binary form 1010100110 supports bitwise reasoning, hexadecimal 2A6 aligns with computing notation, and the Roman numeral DCLXXVIII keeps the encyclopedic tradition alive. These attributes make 678 useful for math olympiad problems, puzzle design, and code challenges alike.

Context

Where 678 shows up

Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (673683) to tune search ranges, and educators feature 678 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 678 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 678

Is 678 a prime number?

678 is composite with 8 total factors and the prime factorization 2 × 3 × 113.

What is the prime factorization of 678?

It breaks down as 2 × 3 × 113, multiplying the primes 2 × 3 × 113.

How is 678 represented in binary and hexadecimal?

678 converts to 1010100110 in binary and 2A6 in hexadecimal, which are helpful for computer science applications.

Is 678 a perfect square, cube, or triangular number?

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

What are the digit sum and digital root of 678?

The digits sum to 21, producing a digital root of 3. These tests power divisibility shortcuts for 3 and 9.