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Composite Number

2121

2121 is a odd composite number that follows 2120 and precedes 2122. It is composed of 8 distinct factors: 1, 3, 7, 21, 101, 303, 707, 2121. Its prime factorization can be written as 3 × 7 × 101. 2121 is classified as a deficient number based on the sum of its proper divisors. In computer science, 2121 is represented as 100001001001 in binary and 849 in hexadecimal. Historically, it is written as MMCXXI in Roman numerals.

Roman Numeral
MMCXXI
LatinClassic
Binary
100001001001
Base 2
Hexadecimal
849
Base 16

Factor Analysis

8 Factors

Properties

ParityOdd
Perfect SquareNo
Perfect CubeNo
Digit Count4
Digit Sum6
Digital Root6
Sum of Factors3264
Aliquot Sum1143
ClassificationDeficient
Prime Factors3
SequencesComposite numbers, Deficient numbers
Prime Factorization

The prime factorization (3 × 7 × 101) reveals 3 prime building blocks.

Canonical form
3 × 7 × 101
37101
Divisibility Insights
  • Divisible by 2

    2121 ends in 1, so it is odd.

  • Divisible by 3

    The digit sum 6 is a multiple of 3.

  • Divisible by 4

    The last two digits 21 are not divisible by 4.

  • Divisible by 5

    2121 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 6 is not a multiple of 9.

  • Divisible by 10

    2121 does not end in 0.

  • Divisible by 11

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

Sequence Membership

Deficient classification and digit analytics place 2121 within several notable number theory sequences:

Composite numbersDeficient numbers
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Deep dive

How 2121 breaks down

2121 carries 8 distinct factors and a digit signature of 6 (6 as the digital root). The deficient classification indicates that its proper divisors sum to 1143, which stays below the number, offering a quick glimpse into its abundance profile.

Numeral conversions provide additional context: the binary form 100001001001 supports bitwise reasoning, hexadecimal 849 aligns with computing notation, and the Roman numeral MMCXXI keeps the encyclopedic tradition alive. These attributes make 2121 useful for math olympiad problems, puzzle design, and code challenges alike.

Context

Where 2121 shows up

Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (21162126) to tune search ranges, and educators feature 2121 in worksheets about factor trees. Its binary footprint of length 12 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 2121 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 2121

Is 2121 a prime number?

2121 is composite with 8 total factors and the prime factorization 3 × 7 × 101.

What is the prime factorization of 2121?

It breaks down as 3 × 7 × 101, multiplying the primes 3 × 7 × 101.

How is 2121 represented in binary and hexadecimal?

2121 converts to 100001001001 in binary and 849 in hexadecimal, which are helpful for computer science applications.

Is 2121 a perfect square, cube, or triangular number?

2121 is not a perfect square, is not a perfect cube, and is not triangular.

What are the digit sum and digital root of 2121?

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