4
4 is a even composite number that follows 3 and precedes 5. It is composed of 3 distinct factors: 1, 2, 4. Its prime factorization can be written as 2^2. 4 is classified as a deficient number based on the sum of its proper divisors. In computer science, 4 is represented as 100 in binary and 4 in hexadecimal. Historically, it is written as IV in Roman numerals. It also belongs to the perfect square sequence.
Factor Analysis
3 FactorsProperties
The prime factorization (2^2) reveals 2 prime building blocks.
Divisible by 2
4 ends in 4, so it is even.
Divisible by 3
The digit sum 4 is not a multiple of 3.
Divisible by 4
The last two digits 04 form a multiple of 4.
Divisible by 5
4 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 4 is not a multiple of 9.
Divisible by 10
4 does not end in 0.
Divisible by 11
The alternating digit sum 4 is not a multiple of 11.
Deficient classification and digit analytics place 4 within several notable number theory sequences:
Timeline
Deep dive
How 4 breaks down
4 carries 3 distinct factors and a digit signature of 4 (4 as the digital root). The deficient classification indicates that its proper divisors sum to 3, which stays below the number, offering a quick glimpse into its abundance profile.
Numeral conversions provide additional context: the binary form 100 supports bitwise reasoning, hexadecimal 4 aligns with computing notation, and the Roman numeral IV keeps the encyclopedic tradition alive. These attributes make 4 useful for math olympiad problems, puzzle design, and code challenges alike.
Context
Where 4 shows up
Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (1–9) to tune search ranges, and educators feature 4 in worksheets about factor trees. Its binary footprint of length 3 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) help historians, numerologists, and trivia writers tie 4 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 4
Is 4 a prime number?
4 is composite with 3 total factors and the prime factorization 2^2.
What is the prime factorization of 4?
It breaks down as 2^2, multiplying the primes 2 × 2.
How is 4 represented in binary and hexadecimal?
4 converts to 100 in binary and 4 in hexadecimal, which are helpful for computer science applications.
Is 4 a perfect square, cube, or triangular number?
4 is a perfect square, is not a perfect cube, and is not triangular.
What are the digit sum and digital root of 4?
The digits sum to 4, producing a digital root of 4. These tests power divisibility shortcuts for 3 and 9.