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Composite Number

1591

1591 is a odd composite number that follows 1590 and precedes 1592. It is composed of 4 distinct factors: 1, 37, 43, 1591. Its prime factorization can be written as 37 × 43. 1591 is classified as a deficient number based on the sum of its proper divisors. In computer science, 1591 is represented as 11000110111 in binary and 637 in hexadecimal. Historically, it is written as MDXCI in Roman numerals.

Roman Numeral
MDXCI
LatinClassic
Binary
11000110111
Base 2
Hexadecimal
637
Base 16

Factor Analysis

4 Factors

Properties

ParityOdd
Perfect SquareNo
Perfect CubeNo
Digit Count4
Digit Sum16
Digital Root7
Sum of Factors1672
Aliquot Sum81
ClassificationDeficient
Prime Factors2
SequencesComposite numbers, Deficient numbers
Prime Factorization

The prime factorization (37 × 43) reveals 2 prime building blocks.

Canonical form
37 × 43
3743
Divisibility Insights
  • Divisible by 2

    1591 ends in 1, so it is odd.

  • Divisible by 3

    The digit sum 16 is not a multiple of 3.

  • Divisible by 4

    The last two digits 91 are not divisible by 4.

  • Divisible by 5

    1591 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 16 is not a multiple of 9.

  • Divisible by 10

    1591 does not end in 0.

  • Divisible by 11

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

Sequence Membership

Deficient classification and digit analytics place 1591 within several notable number theory sequences:

Composite numbersDeficient numbers
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Deep dive

How 1591 breaks down

1591 carries 4 distinct factors and a digit signature of 16 (7 as the digital root). The deficient classification indicates that its proper divisors sum to 81, which stays below the number, offering a quick glimpse into its abundance profile.

Numeral conversions provide additional context: the binary form 11000110111 supports bitwise reasoning, hexadecimal 637 aligns with computing notation, and the Roman numeral MDXCI keeps the encyclopedic tradition alive. These attributes make 1591 useful for math olympiad problems, puzzle design, and code challenges alike.

Context

Where 1591 shows up

Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (15861596) to tune search ranges, and educators feature 1591 in worksheets about factor trees. Its binary footprint of length 11 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 1591 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 1591

Is 1591 a prime number?

1591 is composite with 4 total factors and the prime factorization 37 × 43.

What is the prime factorization of 1591?

It breaks down as 37 × 43, multiplying the primes 37 × 43.

How is 1591 represented in binary and hexadecimal?

1591 converts to 11000110111 in binary and 637 in hexadecimal, which are helpful for computer science applications.

Is 1591 a perfect square, cube, or triangular number?

1591 is not a perfect square, is not a perfect cube, and is not triangular.

What are the digit sum and digital root of 1591?

The digits sum to 16, producing a digital root of 7. These tests power divisibility shortcuts for 3 and 9.