The number 6840
6840 is a composite number with 48 divisors. Its prime factorisation is × × 5 × 19. Divisors (48): 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 19, 20, 24, 30 … 6840.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 6840: a Harshad number: divisible by its digit sum 18.
- 2
6840 is composite. Its prime factorisation is
- 3
The divisors add up to 23400; without 6840 itself that is 16560, so 6840 is abundant (16560 is more than 6840). Euler's totient φ(6840) = 1728 numbers up to 6840 share no factor with it.
- 4
The digits of 6840 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 57 steps to reach 1.
LaTeX source of the formulas on this page
\[ 6840 = 2^{3} \times 3^{2} \times 5 \times 19 \]6840 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 48 |
| Sum of divisors | 23400 |
| Euler totient φ(n) | 1728 |
| Square | 46785600 |
| Cube | 320013504000 |
| Square root | 82.704293 (= 6√190) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 57 |
| Scientific notation | 6.84 × |
6840 in other forms
| Form | Value |
|---|---|
| In words | six thousand eight hundred and forty |
| Binary (base 2) | 1101010111000 |
| Octal (base 8) | 15270 |
| Hexadecimal (base 16) | 1AB8 |
| Base 3 | 100101100 |
| As time | 6840 seconds = 1 h 54 min 0 s |
Is 6840 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (6840 ÷ 2 = 3420) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (6840 ÷ 3 = 2280) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (6840 ÷ 4 = 1710) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (6840 ÷ 5 = 1368) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (6840 ÷ 6 = 1140) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 1) | 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 | Yes (6840 ÷ 8 = 855) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (6840 ÷ 9 = 760) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (6840 ÷ 10 = 684) | 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 | Yes (6840 ÷ 12 = 570) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 6840 a prime number?
No. 6840 = × × 5 × 19, so it is divisible by 2.
What are the factors of 6840?
1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 19, 20, 24, 30, 36, 38, 40, 45, 57, 60, 72, 76, 90, 95, 114, 120, 152, 171, 180, 190, 228, 285, 342, 360, 380, 456, 570, 684, 760, 855, 1140, 1368, 1710, 2280, 3420, 6840.
What is 6840 in binary?
1101010111000 (hexadecimal 1AB8, octal 15270).
What is the square root of 6840?
About 82.7043, exactly 6√190.
Is 6840 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 6840?
6840 is a Harshad number: divisible by its digit sum 18.