The number 6404
6404 is a composite number with 6 divisors. Its prime factorisation is × 1601. Divisors (6): 1, 2, 4, 1601, 3202, 6404.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 6404: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
6404 is composite. Its prime factorisation is
- 3
The divisors add up to 11214; without 6404 itself that is 4810, so 6404 is deficient (4810 is less than 6404). Euler's totient φ(6404) = 3200 numbers up to 6404 share no factor with it.
- 4
The digits of 6404 add up to 14, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 62 steps to reach 1.
LaTeX source of the formulas on this page
\[ 6404 = 2^{2} \times 1601 \]6404 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 11214 |
| Euler totient φ(n) | 3200 |
| Square | 41011216 |
| Cube | 262635827264 |
| Square root | 80.024996 (= 2√1601) |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 62 |
| Scientific notation | 6.404 × |
6404 in other forms
| Form | Value |
|---|---|
| In words | six thousand four hundred and four |
| Binary (base 2) | 1100100000100 |
| Octal (base 8) | 14404 |
| Hexadecimal (base 16) | 1904 |
| Base 3 | 22210012 |
| As time | 6404 seconds = 1 h 46 min 44 s |
Is 6404 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (6404 ÷ 2 = 3202) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 2) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (6404 ÷ 4 = 1601) | 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 2) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 6) | 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 4) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 4) | 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 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 6404 a prime number?
No. 6404 = × 1601, so it is divisible by 2.
What are the factors of 6404?
1, 2, 4, 1601, 3202, 6404.
What is 6404 in binary?
1100100000100 (hexadecimal 1904, octal 14404).
What is the square root of 6404?
About 80.0250, exactly 2√1601.
Is 6404 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 6404?
6404 is a happy number: repeatedly adding the squares of its digits reaches 1.