The number 13720
13720 is a composite number with 32 divisors. Its prime factorisation is × 5 × . Divisors (32): 1, 2, 4, 5, 7, 8, 10, 14, 20, 28, 35, 40, 49, 56, 70, 98 … 13720.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
13720 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
13720 is composite. Its prime factorisation is
- 3
The divisors add up to 36000; without 13720 itself that is 22280, so 13720 is abundant (22280 is more than 13720). Euler's totient φ(13720) = 4704 numbers up to 13720 share no factor with it.
- 4
The digits of 13720 add up to 13, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 32 steps to reach 1.
LaTeX source of the formulas on this page
\[ 13720 = 2^{3} \times 5 \times 7^{3} \]13720 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 32 |
| Sum of divisors | 36000 |
| Euler totient φ(n) | 4704 |
| Square | 188238400 |
| Cube | 2582630848000 |
| Square root | 117.132404 (= 14√70) |
| Digit sum / digital root | 13 / 4 |
| Collatz steps to 1 | 32 |
| Scientific notation | 1.372 × |
13720 in other forms
| Form | Value |
|---|---|
| In words | thirteen thousand seven hundred and twenty |
| Binary (base 2) | 11010110011000 |
| Octal (base 8) | 32630 |
| Hexadecimal (base 16) | 3598 |
| Base 3 | 200211011 |
| As time | 13720 seconds = 3 h 48 min 40 s |
Is 13720 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (13720 ÷ 2 = 6860) | 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 | Yes (13720 ÷ 4 = 3430) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (13720 ÷ 5 = 2744) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (13720 ÷ 7 = 1960) | 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 | Yes (13720 ÷ 8 = 1715) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 4) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (13720 ÷ 10 = 1372) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 13720 a prime number?
No. 13720 = × 5 × , so it is divisible by 2.
What are the factors of 13720?
1, 2, 4, 5, 7, 8, 10, 14, 20, 28, 35, 40, 49, 56, 70, 98, 140, 196, 245, 280, 343, 392, 490, 686, 980, 1372, 1715, 1960, 2744, 3430, 6860, 13720.
What is 13720 in binary?
11010110011000 (hexadecimal 3598, octal 32630).
What is the square root of 13720?
About 117.1324, exactly 14√70.
Is 13720 divisible by 3?
No. Its digits add up to 13, which is not a multiple of 3.
What is special about the number 13720?
It is a composite number with 32 divisors.