The number 13809
13809 is a composite number with 4 divisors. Its prime factorisation is 3 × 4603. Divisors (4): 1, 3, 4603, 13809.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 13809: a semiprime: 3 × 4603, the product of two primes.
- 2
13809 is composite. Its prime factorisation is
- 3
The divisors add up to 18416; without 13809 itself that is 4607, so 13809 is deficient (4607 is less than 13809). Euler's totient φ(13809) = 9204 numbers up to 13809 share no factor with it.
- 4
The digits of 13809 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 45 steps to reach 1.
LaTeX source of the formulas on this page
\[ 13809 = 3 \times 4603 \]
13809 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 18416 |
| Euler totient φ(n) | 9204 |
| Square | 190688481 |
| Cube | 2633217234129 |
| Square root | 117.511702 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 45 |
| Scientific notation | 1.3809 × |
13809 in other forms
| Form | Value |
|---|---|
| In words | thirteen thousand eight hundred and nine |
| Binary (base 2) | 11010111110001 |
| Octal (base 8) | 32761 |
| Hexadecimal (base 16) | 35F1 |
| Base 3 | 200221110 |
| As time | 13809 seconds = 3 h 50 min 9 s |
Is 13809 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 (13809 ÷ 3 = 4603) | 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 | 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 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 4) | 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 13809 a prime number?
No. 13809 = 3 × 4603, so it is divisible by 3.
What are the factors of 13809?
1, 3, 4603, 13809.
What is 13809 in binary?
11010111110001 (hexadecimal 35F1, octal 32761).
What is the square root of 13809?
About 117.5117.
Is 13809 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 13809?
13809 is a semiprime: 3 × 4603, the product of two primes.