The number 6409
6409 is a composite number with 8 divisors. Its prime factorisation is 13 × 17 × 29. Divisors (8): 1, 13, 17, 29, 221, 377, 493, 6409.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 6409: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
6409 is composite. Its prime factorisation is
- 3
The divisors add up to 7560; without 6409 itself that is 1151, so 6409 is deficient (1151 is less than 6409). Euler's totient φ(6409) = 5376 numbers up to 6409 share no factor with it.
- 4
The digits of 6409 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 124 steps to reach 1.
LaTeX source of the formulas on this page
\[ 6409 = 13 \times 17 \times 29 \]
6409 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 7560 |
| Euler totient φ(n) | 5376 |
| Square | 41075281 |
| Cube | 263251475929 |
| Square root | 80.056230 |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 124 |
| Scientific notation | 6.409 × |
6409 in other forms
| Form | Value |
|---|---|
| In words | six thousand four hundred and nine |
| Binary (base 2) | 1100100001001 |
| Octal (base 8) | 14411 |
| Hexadecimal (base 16) | 1909 |
| Base 3 | 22210101 |
| As time | 6409 seconds = 1 h 46 min 49 s |
Is 6409 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 | No (remainder 1) | 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 1) | 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | 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 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 6409 a prime number?
No. 6409 = 13 × 17 × 29, so it is divisible by 13.
What are the factors of 6409?
1, 13, 17, 29, 221, 377, 493, 6409.
What is 6409 in binary?
1100100001001 (hexadecimal 1909, octal 14411).
What is the square root of 6409?
About 80.0562.
Is 6409 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 6409?
6409 is a happy number: repeatedly adding the squares of its digits reaches 1.