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Prime Number

43

43 is a odd prime number that follows 42 and precedes 44. As a prime number, 43 is only divisible by 1 and itself. It holds a unique position in the sequence of integers. Its prime factorization is simply 43. 43 is classified as a deficient number based on the sum of its proper divisors. In computer science, 43 is represented as 101011 in binary and 2B in hexadecimal. Historically, it is written as XLIII in Roman numerals.

Roman Numeral
XLIII
LatinClassic
Binary
101011
Base 2
Hexadecimal
2B
Base 16

Factor Analysis

2 Factors

Properties

ParityOdd
Perfect SquareNo
Perfect CubeNo
Digit Count2
Digit Sum7
Digital Root7
Sum of Factors44
Aliquot Sum1
ClassificationDeficient
Prime Factors1
SequencesPrime numbers, Deficient numbers
Prime Factorization

43 is prime, so its only factors are 1 and 43.

Canonical form
43
43
Divisibility Insights
  • Divisible by 2

    43 ends in 3, so it is odd.

  • Divisible by 3

    The digit sum 7 is not a multiple of 3.

  • Divisible by 4

    The last two digits 43 are not divisible by 4.

  • Divisible by 5

    43 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 7 is not a multiple of 9.

  • Divisible by 10

    43 does not end in 0.

  • Divisible by 11

    The alternating digit sum 1 is not a multiple of 11.

Sequence Membership

Deficient classification and digit analytics place 43 within several notable number theory sequences:

Prime numbersDeficient numbers
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Deep dive

How 43 breaks down

43 carries 2 distinct factors and a digit signature of 7 (7 as the digital root). The deficient classification indicates that its proper divisors sum to 1, which stays below the number, offering a quick glimpse into its abundance profile.

Numeral conversions provide additional context: the binary form 101011 supports bitwise reasoning, hexadecimal 2B aligns with computing notation, and the Roman numeral XLIII keeps the encyclopedic tradition alive. These attributes make 43 useful for math olympiad problems, puzzle design, and code challenges alike.

Context

Where 43 shows up

Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (3848) to tune search ranges, and educators feature 43 in worksheets about prime identification. 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 (Prime numbers, Deficient numbers) help historians, numerologists, and trivia writers tie 43 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 43

Is 43 a prime number?

43 is prime, meaning it is only divisible by 1 and itself.

What is the prime factorization of 43?

43 is already prime, so the factorization is simply 43.

How is 43 represented in binary and hexadecimal?

43 converts to 101011 in binary and 2B in hexadecimal, which are helpful for computer science applications.

Is 43 a perfect square, cube, or triangular number?

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

What are the digit sum and digital root of 43?

The digits sum to 7, producing a digital root of 7. These tests power divisibility shortcuts for 3 and 9.