491
491 is a odd prime number that follows 490 and precedes 492. As a prime number, 491 is only divisible by 1 and itself. It holds a unique position in the sequence of integers. Its prime factorization is simply 491. 491 is classified as a deficient number based on the sum of its proper divisors. In computer science, 491 is represented as 111101011 in binary and 1EB in hexadecimal. Historically, it is written as CDXCI in Roman numerals.
Factor Analysis
2 FactorsProperties
491 is prime, so its only factors are 1 and 491.
Divisible by 2
491 ends in 1, so it is odd.
Divisible by 3
The digit sum 14 is not a multiple of 3.
Divisible by 4
The last two digits 91 are not divisible by 4.
Divisible by 5
491 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 14 is not a multiple of 9.
Divisible by 10
491 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 491 within several notable number theory sequences:
Timeline
Deep dive
How 491 breaks down
491 carries 2 distinct factors and a digit signature of 14 (5 as the digital root). The deficient classification indicates that its proper divisors sum to 1, which stays below the number, offering a quick glimpse into its abundance profile.
Numeral conversions provide additional context: the binary form 111101011 supports bitwise reasoning, hexadecimal 1EB aligns with computing notation, and the Roman numeral CDXCI keeps the encyclopedic tradition alive. These attributes make 491 useful for math olympiad problems, puzzle design, and code challenges alike.
Context
Where 491 shows up
Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (486–496) to tune search ranges, and educators feature 491 in worksheets about prime identification. Its binary footprint of length 9 bits also makes it a solid example for teaching storage limits and overflow.
Beyond STEM, the classification and sequence tags (Prime numbers, Deficient numbers) help historians, numerologists, and trivia writers tie 491 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 491
Is 491 a prime number?
491 is prime, meaning it is only divisible by 1 and itself.
What is the prime factorization of 491?
491 is already prime, so the factorization is simply 491.
How is 491 represented in binary and hexadecimal?
491 converts to 111101011 in binary and 1EB in hexadecimal, which are helpful for computer science applications.
Is 491 a perfect square, cube, or triangular number?
491 is not a perfect square, is not a perfect cube, and is not triangular.
What are the digit sum and digital root of 491?
The digits sum to 14, producing a digital root of 5. These tests power divisibility shortcuts for 3 and 9.