The number 13870
13870 is a composite number with 16 divisors. Its prime factorisation is 2 × 5 × 19 × 73. Divisors (16): 1, 2, 5, 10, 19, 38, 73, 95, 146, 190, 365, 730, 1387, 2774, 6935, 13870.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 13870: a Harshad number: divisible by its digit sum 19.
- 2
13870 is composite. Its prime factorisation is
- 3
The divisors add up to 26640; without 13870 itself that is 12770, so 13870 is deficient (12770 is less than 13870). Euler's totient φ(13870) = 5184 numbers up to 13870 share no factor with it.
- 4
The digits of 13870 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 151 steps to reach 1.
LaTeX source of the formulas on this page
\[ 13870 = 2 \times 5 \times 19 \times 73 \]
13870 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 26640 |
| Euler totient φ(n) | 5184 |
| Square | 192376900 |
| Cube | 2668267603000 |
| Square root | 117.770964 |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 151 |
| Scientific notation | 1.387 × |
13870 in other forms
| Form | Value |
|---|---|
| In words | thirteen thousand eight hundred and seventy |
| Binary (base 2) | 11011000101110 |
| Octal (base 8) | 33056 |
| Hexadecimal (base 16) | 362E |
| Base 3 | 201000201 |
| As time | 13870 seconds = 3 h 51 min 10 s |
Is 13870 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (13870 ÷ 2 = 6935) | 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 | No (remainder 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (13870 ÷ 5 = 2774) | 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 | No (remainder 3) | 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 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (13870 ÷ 10 = 1387) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 10) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 13870 a prime number?
No. 13870 = 2 × 5 × 19 × 73, so it is divisible by 2.
What are the factors of 13870?
1, 2, 5, 10, 19, 38, 73, 95, 146, 190, 365, 730, 1387, 2774, 6935, 13870.
What is 13870 in binary?
11011000101110 (hexadecimal 362E, octal 33056).
What is the square root of 13870?
About 117.7710.
Is 13870 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 13870?
13870 is a Harshad number: divisible by its digit sum 19.