The number 12801
12801 is a composite number with 8 divisors. Its prime factorisation is 3 × 17 × 251. Divisors (8): 1, 3, 17, 51, 251, 753, 4267, 12801.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 12801: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
12801 is composite. Its prime factorisation is
- 3
The divisors add up to 18144; without 12801 itself that is 5343, so 12801 is deficient (5343 is less than 12801). Euler's totient φ(12801) = 8000 numbers up to 12801 share no factor with it.
- 4
The digits of 12801 add up to 12, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 169 steps to reach 1.
LaTeX source of the formulas on this page
\[ 12801 = 3 \times 17 \times 251 \]
12801 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 18144 |
| Euler totient φ(n) | 8000 |
| Square | 163865601 |
| Cube | 2097643558401 |
| Square root | 113.141504 |
| Digit sum / digital root | 12 / 3 |
| Collatz steps to 1 | 169 |
| Scientific notation | 1.2801 × |
12801 in other forms
| Form | Value |
|---|---|
| In words | twelve thousand eight hundred and one |
| Binary (base 2) | 11001000000001 |
| Octal (base 8) | 31001 |
| Hexadecimal (base 16) | 3201 |
| Base 3 | 122120010 |
| As time | 12801 seconds = 3 h 33 min 21 s |
Is 12801 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 (12801 ÷ 3 = 4267) | 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 5) | 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 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | 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 12801 a prime number?
No. 12801 = 3 × 17 × 251, so it is divisible by 3.
What are the factors of 12801?
1, 3, 17, 51, 251, 753, 4267, 12801.
What is 12801 in binary?
11001000000001 (hexadecimal 3201, octal 31001).
What is the square root of 12801?
About 113.1415.
Is 12801 divisible by 3?
Yes. Its digits add up to 12, a multiple of 3.
What is special about the number 12801?
12801 is a happy number: repeatedly adding the squares of its digits reaches 1.