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Composite Number

1

1 is a odd composite number that follows 0 and precedes 2. It is composed of 1 distinct factors: 1. Its prime factorization can be written as 1. 1 is classified as a deficient number based on the sum of its proper divisors. In computer science, 1 is represented as 1 in binary and 1 in hexadecimal. Historically, it is written as I in Roman numerals. It also belongs to the perfect square, perfect cube, triangular number, Fibonacci number sequences.

Roman Numeral
I
LatinClassic
Binary
1
Base 2
Hexadecimal
1
Base 16

Factor Analysis

1 Factors

Properties

ParityOdd
Perfect SquareYes
Perfect CubeYes
Digit Count1
Digit Sum1
Digital Root1
Sum of Factors1
Aliquot Sum0
ClassificationDeficient
Prime Factors0
SequencesComposite numbers, Deficient numbers
Prime Factorization

The prime factorization (1) reveals 0 prime building blocks.

Canonical form
1
No prime factors (unity)
Divisibility Insights
  • Divisible by 2

    1 ends in 1, so it is odd.

  • Divisible by 3

    The digit sum 1 is not a multiple of 3.

  • Divisible by 4

    The last two digits 01 are not divisible by 4.

  • Divisible by 5

    1 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 1 is not a multiple of 9.

  • Divisible by 10

    1 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 1 within several notable number theory sequences:

Composite numbersDeficient numbersPerfect squaresPerfect cubesTriangular numbersFibonacci numbers

Timeline

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Deep dive

How 1 breaks down

1 carries 1 distinct factors and a digit signature of 1 (1 as the digital root). The deficient classification indicates that its proper divisors sum to 0, which stays below the number, offering a quick glimpse into its abundance profile.

Numeral conversions provide additional context: the binary form 1 supports bitwise reasoning, hexadecimal 1 aligns with computing notation, and the Roman numeral I keeps the encyclopedic tradition alive. These attributes make 1 useful for math olympiad problems, puzzle design, and code challenges alike.

Context

Where 1 shows up

Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (26) to tune search ranges, and educators feature 1 in worksheets about factor trees. Its binary footprint of length 1 bits also makes it a solid example for teaching storage limits and overflow.

Beyond STEM, the classification and sequence tags (Composite numbers, Deficient numbers, Perfect squares, Perfect cubes, Triangular numbers, Fibonacci numbers) help historians, numerologists, and trivia writers tie 1 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 1

Is 1 a prime number?

1 is composite with 1 total factors and the prime factorization 1.

What is the prime factorization of 1?

It breaks down as 1, multiplying the primes .

How is 1 represented in binary and hexadecimal?

1 converts to 1 in binary and 1 in hexadecimal, which are helpful for computer science applications.

Is 1 a perfect square, cube, or triangular number?

1 is a perfect square, is a perfect cube, and is triangular. It also belongs to the Fibonacci sequence.

What are the digit sum and digital root of 1?

The digits sum to 1, producing a digital root of 1. These tests power divisibility shortcuts for 3 and 9.