The number 1131
1131 is a composite number with 8 divisors. Its prime factorisation is 3 × 13 × 29. Divisors (8): 1, 3, 13, 29, 39, 87, 377, 1131.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
1131 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
1131 is composite. Its prime factorisation is
- 3
The divisors add up to 1680; without 1131 itself that is 549, so 1131 is deficient (549 is less than 1131). Euler's totient φ(1131) = 672 numbers up to 1131 share no factor with it.
- 4
The digits of 1131 add up to 6, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 36 steps to reach 1.
LaTeX source of the formulas on this page
\[ 1131 = 3 \times 13 \times 29 \]
1131 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 1680 |
| Euler totient φ(n) | 672 |
| Square | 1279161 |
| Cube | 1446731091 |
| Square root | 33.630343 |
| Digit sum / digital root | 6 / 6 |
| Collatz steps to 1 | 36 |
| Scientific notation | 1.131 × |
1131 in other forms
| Form | Value |
|---|---|
| In words | one thousand one hundred and thirty-one |
| Roman numerals | MCXXXI |
| Binary (base 2) | 10001101011 |
| Octal (base 8) | 2153 |
| Hexadecimal (base 16) | 46B |
| Base 3 | 1112220 |
| As time | 1131 seconds = 18 min 51 s |
Is 1131 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (1131 ÷ 3 = 377) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 4) | A number is divisible by 7 if double the last digit and subtract it from the rest: the result is a multiple of 7. |
| 8 | No (remainder 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 1131 a prime number?
No. 1131 = 3 × 13 × 29, so it is divisible by 3.
What are the factors of 1131?
1, 3, 13, 29, 39, 87, 377, 1131.
What is 1131 in binary?
10001101011 (hexadecimal 46B, octal 2153).
What is the square root of 1131?
About 33.6303.
What is 1131 in Roman numerals?
MCXXXI.
Is 1131 divisible by 3?
Yes. Its digits add up to 6, a multiple of 3.
What is special about the number 1131?
It is a composite number with 8 divisors.