The number 4809
4809 is a composite number with 8 divisors. Its prime factorisation is 3 × 7 × 229. Divisors (8): 1, 3, 7, 21, 229, 687, 1603, 4809.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 4809: a Harshad number: divisible by its digit sum 21.
- 2
4809 is composite. Its prime factorisation is
- 3
The divisors add up to 7360; without 4809 itself that is 2551, so 4809 is deficient (2551 is less than 4809). Euler's totient φ(4809) = 2736 numbers up to 4809 share no factor with it.
- 4
The digits of 4809 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 46 steps to reach 1.
LaTeX source of the formulas on this page
\[ 4809 = 3 \times 7 \times 229 \]
4809 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 7360 |
| Euler totient φ(n) | 2736 |
| Square | 23126481 |
| Cube | 111215247129 |
| Square root | 69.346954 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 46 |
| Scientific notation | 4.809 × |
4809 in other forms
| Form | Value |
|---|---|
| In words | four thousand eight hundred and nine |
| Binary (base 2) | 1001011001001 |
| Octal (base 8) | 11311 |
| Hexadecimal (base 16) | 12C9 |
| Base 3 | 20121010 |
| As time | 4809 seconds = 1 h 20 min 9 s |
Is 4809 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 (4809 ÷ 3 = 1603) | 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 4) | 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 | Yes (4809 ÷ 7 = 687) | 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 2) | 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 4809 a prime number?
No. 4809 = 3 × 7 × 229, so it is divisible by 3.
What are the factors of 4809?
1, 3, 7, 21, 229, 687, 1603, 4809.
What is 4809 in binary?
1001011001001 (hexadecimal 12C9, octal 11311).
What is the square root of 4809?
About 69.3470.
Is 4809 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 4809?
4809 is a Harshad number: divisible by its digit sum 21.