1191
1191 is a odd composite number that follows 1190 and precedes 1192. It is composed of 4 distinct factors: 1, 3, 397, 1191. Its prime factorization can be written as 3 × 397. 1191 is classified as a deficient number based on the sum of its proper divisors. In computer science, 1191 is represented as 10010100111 in binary and 4A7 in hexadecimal. Historically, it is written as MCXCI in Roman numerals.
Factor Analysis
4 FactorsProperties
The prime factorization (3 × 397) reveals 2 prime building blocks.
Divisible by 2
1191 ends in 1, so it is odd.
Divisible by 3
The digit sum 12 is a multiple of 3.
Divisible by 4
The last two digits 91 are not divisible by 4.
Divisible by 5
1191 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 12 is not a multiple of 9.
Divisible by 10
1191 does not end in 0.
Divisible by 11
The alternating digit sum 8 is not a multiple of 11.
Deficient classification and digit analytics place 1191 within several notable number theory sequences:
Timeline
Deep dive
How 1191 breaks down
1191 carries 4 distinct factors and a digit signature of 12 (3 as the digital root). The deficient classification indicates that its proper divisors sum to 401, which stays below the number, offering a quick glimpse into its abundance profile.
Numeral conversions provide additional context: the binary form 10010100111 supports bitwise reasoning, hexadecimal 4A7 aligns with computing notation, and the Roman numeral MCXCI keeps the encyclopedic tradition alive. These attributes make 1191 useful for math olympiad problems, puzzle design, and code challenges alike.
Context
Where 1191 shows up
Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (1186–1196) to tune search ranges, and educators feature 1191 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 1191 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 1191
Is 1191 a prime number?
1191 is composite with 4 total factors and the prime factorization 3 × 397.
What is the prime factorization of 1191?
It breaks down as 3 × 397, multiplying the primes 3 × 397.
How is 1191 represented in binary and hexadecimal?
1191 converts to 10010100111 in binary and 4A7 in hexadecimal, which are helpful for computer science applications.
Is 1191 a perfect square, cube, or triangular number?
1191 is not a perfect square, is not a perfect cube, and is not triangular.
What are the digit sum and digital root of 1191?
The digits sum to 12, producing a digital root of 3. These tests power divisibility shortcuts for 3 and 9.