7991
7991 is a odd composite number that follows 7990 and precedes 7992. It is composed of 4 distinct factors: 1, 61, 131, 7991. Its prime factorization can be written as 61 × 131. 7991 is classified as a deficient number based on the sum of its proper divisors. In computer science, 7991 is represented as 1111100110111 in binary and 1F37 in hexadecimal.
Factor Analysis
4 FactorsProperties
The prime factorization (61 × 131) reveals 2 prime building blocks.
Divisible by 2
7991 ends in 1, so it is odd.
Divisible by 3
The digit sum 26 is not a multiple of 3.
Divisible by 4
The last two digits 91 are not divisible by 4.
Divisible by 5
7991 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 26 is not a multiple of 9.
Divisible by 10
7991 does not end in 0.
Divisible by 11
The alternating digit sum 6 is not a multiple of 11.
Deficient classification and digit analytics place 7991 within several notable number theory sequences:
Timeline
Deep dive
How 7991 breaks down
7991 carries 4 distinct factors and a digit signature of 26 (8 as the digital root). The deficient classification indicates that its proper divisors sum to 193, which stays below the number, offering a quick glimpse into its abundance profile.
Numeral conversions provide additional context: the binary form 1111100110111 supports bitwise reasoning, hexadecimal 1F37 aligns with computing notation, and the Roman numeral N/A (1-3999) keeps the encyclopedic tradition alive. These attributes make 7991 useful for math olympiad problems, puzzle design, and code challenges alike.
Context
Where 7991 shows up
Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (7986–7996) to tune search ranges, and educators feature 7991 in worksheets about factor trees. Its binary footprint of length 13 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 7991 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 7991
Is 7991 a prime number?
7991 is composite with 4 total factors and the prime factorization 61 × 131.
What is the prime factorization of 7991?
It breaks down as 61 × 131, multiplying the primes 61 × 131.
How is 7991 represented in binary and hexadecimal?
7991 converts to 1111100110111 in binary and 1F37 in hexadecimal, which are helpful for computer science applications.
Is 7991 a perfect square, cube, or triangular number?
7991 is not a perfect square, is not a perfect cube, and is not triangular.
What are the digit sum and digital root of 7991?
The digits sum to 26, producing a digital root of 8. These tests power divisibility shortcuts for 3 and 9.