123
123 is a odd composite number that follows 122 and precedes 124. It is composed of 4 distinct factors: 1, 3, 41, 123. Its prime factorization can be written as 3 × 41. 123 is classified as a deficient number based on the sum of its proper divisors. In computer science, 123 is represented as 1111011 in binary and 7B in hexadecimal. Historically, it is written as CXXIII in Roman numerals.
Factor Analysis
4 FactorsProperties
The prime factorization (3 × 41) reveals 2 prime building blocks.
Divisible by 2
123 ends in 3, so it is odd.
Divisible by 3
The digit sum 6 is a multiple of 3.
Divisible by 4
The last two digits 23 are not divisible by 4.
Divisible by 5
123 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 6 is not a multiple of 9.
Divisible by 10
123 does not end in 0.
Divisible by 11
The alternating digit sum 2 is not a multiple of 11.
Deficient classification and digit analytics place 123 within several notable number theory sequences:
Timeline
Deep dive
How 123 breaks down
123 carries 4 distinct factors and a digit signature of 6 (6 as the digital root). The deficient classification indicates that its proper divisors sum to 45, which stays below the number, offering a quick glimpse into its abundance profile.
Numeral conversions provide additional context: the binary form 1111011 supports bitwise reasoning, hexadecimal 7B aligns with computing notation, and the Roman numeral CXXIII keeps the encyclopedic tradition alive. These attributes make 123 useful for math olympiad problems, puzzle design, and code challenges alike.
Context
Where 123 shows up
Engineers lean on the divisibility profile when sizing circuits, mod designers use neighboring values (118–128) to tune search ranges, and educators feature 123 in worksheets about factor trees. Its binary footprint of length 7 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 123 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 123
Is 123 a prime number?
123 is composite with 4 total factors and the prime factorization 3 × 41.
What is the prime factorization of 123?
It breaks down as 3 × 41, multiplying the primes 3 × 41.
How is 123 represented in binary and hexadecimal?
123 converts to 1111011 in binary and 7B in hexadecimal, which are helpful for computer science applications.
Is 123 a perfect square, cube, or triangular number?
123 is not a perfect square, is not a perfect cube, and is not triangular.
What are the digit sum and digital root of 123?
The digits sum to 6, producing a digital root of 6. These tests power divisibility shortcuts for 3 and 9.