Number dictionary · Exact arithmetic
731: factors and number facts
seven hundred thirty-one is an odd number and is composite. Its 4 positive divisors form 2 factor pairs.
Number JD Editorial Team · Updated 2026-10-08
- In words
- seven hundred thirty-one
- Roman numeral
- DCCXXXI
- Prime factorization
- 17 × 43
- Digital root
- 2
All factors of 731
A positive factor divides 731 with no remainder. In ascending order, the complete list is:
1, 17, 43, 731
Factor pairs
- 1 × 731 = 731
- 17 × 43 = 731
Each pair describes an arrangement of 731 items into equal rows. The pairs have different row and column counts; 731 cannot make a square array of whole items.
Divisor totals
- Positive divisors
- 4
- Sum of all divisors
- 792
- Sum excluding 731
- 61
- Classification
- deficient
731 is deficient because its proper divisors add to 61, which is less than 731.
Prime factorization of 731
731 = 17 × 43
Repeated division, step by step
- 731 ÷ 17 = 43
- 43 ÷ 43 = 1
Multiply the prime divisors in these steps to reconstruct 731. Each prime in this factorization occurs once. The divisor-count calculation is (1 + 1) × (1 + 1) = 4.
The preceding prime is 727. The next larger prime is 733. The factor list above explains why 731 is composite.
Learn the factorization method731 in words, Roman numerals and other bases
| Representation | Value |
|---|---|
| English (US style) | seven hundred thirty-one |
| Roman numeral | DCCXXXI |
| Binary (base 2) | 1011011011 |
| Octal (base 8) | 1333 |
| Decimal (base 10) | 731 |
| Hexadecimal (base 16) | 2DB |
Check the binary conversion
Read 1011011011 from right to left using place values 1, 2, 4, 8 and successive powers of two. Keep the values whose bit is 1:
512 + 128 + 64 + 16 + 8 + 2 + 1 = 731
Check the hexadecimal conversion
2 × 16^2 + 13 × 16^1 + 11 × 16^0 = 731
Hexadecimal uses A through F for digit values 10 through 15. These notations represent the same quantity; changing the base does not change the integer.
Square, cube and square root of 731
- 731 squared
- 731 × 731 = 534,361
- 731 cubed
- 731 × 731 × 731 = 390,617,891
- Square root
- ≈ 27.037012
- Simplified radical
- √731
731 lies between 729 (27²) and 784 (28²), so it is not a perfect square. It is not a perfect cube.
731 is not triangular: no positive whole-number k satisfies k(k + 1) / 2 = 731.
Distinguish a square from a square rootMultiplication table for 731
These are the first twelve positive multiples. Unlike the finite factor list, the sequence of multiples continues without an upper limit.
Divisibility checks
| Divide by | Whole quotient | Remainder | Divides exactly? |
|---|---|---|---|
| 2 | 365 | 1 | No |
| 3 | 243 | 2 | No |
| 4 | 182 | 3 | No |
| 5 | 146 | 1 | No |
| 6 | 121 | 5 | No |
| 7 | 104 | 3 | No |
| 8 | 91 | 3 | No |
| 9 | 81 | 2 | No |
| 10 | 73 | 1 | No |
| 11 | 66 | 5 | No |
| 12 | 60 | 11 | No |
For example, 731 = 7 × 104 + 3. A remainder of zero is what makes a divisor a factor.
Digit sum and digital root of 731
731 contains 3 decimal digits. Its digit sum is 7 + 3 + 1 = 11.
- 731: 7 + 3 + 1 = 11
- 11: 1 + 1 = 2
The digital root is 2. Reversing its digits gives 137; it is not a decimal palindrome. Digit patterns depend on the notation being used.
Digital-root arithmetic always finishes at a single digit for a positive integer. Some numerology methods stop at 11, 22 or 33 instead; that is a separate interpretive convention.
Fractions and a worked comparison
As a fraction of 100, 731/100 simplifies to 731/100 by dividing both terms by their greatest common divisor, 1. Its decimal value is 7.31. Because the numerator exceeds the denominator, this value is greater than one.
The greatest common divisor of 731 and 12 is 1. Their least common multiple is 8772. The identity GCD × LCM = 731 × 12 = 8772 checks both results.
Work through GCF and LCMQuestions about 731
What are the factors of 731?
The positive factors are 1, 17, 43, 731. There are 4 factors, including 1 and 731.
Is 731 a prime number?
No. 731 is composite: 17 × 43 = 731.
How do you write 731 in Roman numerals?
731 is DCCXXXI in standard subtractive Roman numeral notation.
What is the binary representation of 731?
731 in decimal is 1011011011 in base 2. Adding its active place values gives 512 + 128 + 64 + 16 + 8 + 2 + 1 = 731.
Methods and reference definitions
Number JD calculates each result from the integer on this page. Positive factors are enumerated in pairs; repeated division gives the prime factorization; place values verify base conversions. Decimal square roots are rounded to six places when irrational.
NUMBER JOURNAL / JD
A reflective note on 731
Meaning varies by tradition and personal experience. One sighting is not evidence of what will happen next.
The digits of 731 add to 11. That arithmetic result is separate from the cultural symbolism of the pattern. If this number matters to you, write down what you noticed and choose one grounded action rather than treating the sighting as a prediction.