649
649 is a odd composite number that follows 648 and precedes 650. It is composed of 4 distinct factors: 1, 11, 59, 649. Its prime factorization can be written as 11 × 59. 649 is classified as a deficient number based on the sum of its proper divisors. In computer science, 649 is represented as 1010001001 in binary and 289 in hexadecimal. Historically, it is written as DCXLIX in Roman numerals.
Factor Analysis
4 FactorsProperties
The prime factorization (11 × 59) reveals 2 prime building blocks.
Divisible by 2
649 ends in 9, so it is odd.
Divisible by 3
The digit sum 19 is not a multiple of 3.
Divisible by 4
The last two digits 49 are not divisible by 4.
Divisible by 5
649 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 19 is not a multiple of 9.
Divisible by 10
649 does not end in 0.
Divisible by 11
The alternating digit sum 11 is a multiple of 11.
Deficient classification and digit analytics place 649 within several notable number theory sequences:
Timeline
Deep dive
How 649 breaks down
649 carries 4 distinct factors and a digit signature of 19 (1 as the digital root). The deficient classification indicates that its proper divisors sum to 71, which stays below the number, offering a quick glimpse into its abundance profile.
Numeral conversions provide additional context: the binary form 1010001001 supports bitwise reasoning, hexadecimal 289 aligns with computing notation, and the Roman numeral DCXLIX keeps the encyclopedic tradition alive. These attributes make 649 useful for math olympiad problems, puzzle design, and code challenges alike.
Context
Where 649 shows up
Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (644–654) to tune search ranges, and educators feature 649 in worksheets about factor trees. Its binary footprint of length 10 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 649 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 649
Is 649 a prime number?
649 is composite with 4 total factors and the prime factorization 11 × 59.
What is the prime factorization of 649?
It breaks down as 11 × 59, multiplying the primes 11 × 59.
How is 649 represented in binary and hexadecimal?
649 converts to 1010001001 in binary and 289 in hexadecimal, which are helpful for computer science applications.
Is 649 a perfect square, cube, or triangular number?
649 is not a perfect square, is not a perfect cube, and is not triangular.
What are the digit sum and digital root of 649?
The digits sum to 19, producing a digital root of 1. These tests power divisibility shortcuts for 3 and 9.