The number 6981
6981 is a composite number with 8 divisors. Its prime factorisation is 3 × 13 × 179. Divisors (8): 1, 3, 13, 39, 179, 537, 2327, 6981.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
6981 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
6981 is composite. Its prime factorisation is
- 3
The divisors add up to 10080; without 6981 itself that is 3099, so 6981 is deficient (3099 is less than 6981). Euler's totient φ(6981) = 4272 numbers up to 6981 share no factor with it.
- 4
The digits of 6981 add up to 24, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 150 steps to reach 1.
LaTeX source of the formulas on this page
\[ 6981 = 3 \times 13 \times 179 \]
6981 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 10080 |
| Euler totient φ(n) | 4272 |
| Square | 48734361 |
| Cube | 340214574141 |
| Square root | 83.552379 |
| Digit sum / digital root | 24 / 6 |
| Collatz steps to 1 | 150 |
| Scientific notation | 6.981 × |
6981 in other forms
| Form | Value |
|---|---|
| In words | six thousand nine hundred and eighty-one |
| Binary (base 2) | 1101101000101 |
| Octal (base 8) | 15505 |
| Hexadecimal (base 16) | 1B45 |
| Base 3 | 100120120 |
| As time | 6981 seconds = 1 h 56 min 21 s |
Is 6981 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 (6981 ÷ 3 = 2327) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 1) | 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 2) | 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 5) | 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 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 6981 a prime number?
No. 6981 = 3 × 13 × 179, so it is divisible by 3.
What are the factors of 6981?
1, 3, 13, 39, 179, 537, 2327, 6981.
What is 6981 in binary?
1101101000101 (hexadecimal 1B45, octal 15505).
What is the square root of 6981?
About 83.5524.
Is 6981 divisible by 3?
Yes. Its digits add up to 24, a multiple of 3.
What is special about the number 6981?
It is a composite number with 8 divisors.