The number 13820
13820 is a composite number with 12 divisors. Its prime factorisation is × 5 × 691. Divisors (12): 1, 2, 4, 5, 10, 20, 691, 1382, 2764, 3455, 6910, 13820.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
13820 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
13820 is composite. Its prime factorisation is
- 3
The divisors add up to 29064; without 13820 itself that is 15244, so 13820 is abundant (15244 is more than 13820). Euler's totient φ(13820) = 5520 numbers up to 13820 share no factor with it.
- 4
The digits of 13820 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 58 steps to reach 1.
LaTeX source of the formulas on this page
\[ 13820 = 2^{2} \times 5 \times 691 \]13820 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 29064 |
| Euler totient φ(n) | 5520 |
| Square | 190992400 |
| Cube | 2639514968000 |
| Square root | 117.558496 (= 2√3455) |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 58 |
| Scientific notation | 1.382 × |
13820 in other forms
| Form | Value |
|---|---|
| In words | thirteen thousand eight hundred and twenty |
| Binary (base 2) | 11010111111100 |
| Octal (base 8) | 32774 |
| Hexadecimal (base 16) | 35FC |
| Base 3 | 200221212 |
| As time | 13820 seconds = 3 h 50 min 20 s |
Is 13820 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (13820 ÷ 2 = 6910) | 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 (13820 ÷ 4 = 3455) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (13820 ÷ 5 = 2764) | 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 2) | 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 | Yes (13820 ÷ 10 = 1382) | 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 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 13820 a prime number?
No. 13820 = × 5 × 691, so it is divisible by 2.
What are the factors of 13820?
1, 2, 4, 5, 10, 20, 691, 1382, 2764, 3455, 6910, 13820.
What is 13820 in binary?
11010111111100 (hexadecimal 35FC, octal 32774).
What is the square root of 13820?
About 117.5585, exactly 2√3455.
Is 13820 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 13820?
It is a composite number with 12 divisors.