The number 860
860 is a composite number with 12 divisors. Its prime factorisation is × 5 × 43. Divisors (12): 1, 2, 4, 5, 10, 20, 43, 86, 172, 215, 430, 860.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 860: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
860 is composite. Its prime factorisation is
- 3
The divisors add up to 1848; without 860 itself that is 988, so 860 is abundant (988 is more than 860). Euler's totient φ(860) = 336 numbers up to 860 share no factor with it.
- 4
The digits of 860 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 103 steps to reach 1.
LaTeX source of the formulas on this page
\[ 860 = 2^{2} \times 5 \times 43 \]860 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 1848 |
| Euler totient φ(n) | 336 |
| Square | 739600 |
| Cube | 636056000 |
| Square root | 29.325757 (= 2√215) |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 103 |
| Scientific notation | 8.6 × |
860 in other forms
| Form | Value |
|---|---|
| In words | eight hundred and sixty |
| Roman numerals | DCCCLX |
| Binary (base 2) | 1101011100 |
| Octal (base 8) | 1534 |
| Hexadecimal (base 16) | 35C |
| Base 3 | 1011212 |
| As time | 860 seconds = 14 min 20 s |
Is 860 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (860 ÷ 2 = 430) | 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 (860 ÷ 4 = 215) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (860 ÷ 5 = 172) | 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 6) | 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 (860 ÷ 10 = 86) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 2) | 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 860 a prime number?
No. 860 = × 5 × 43, so it is divisible by 2.
What are the factors of 860?
1, 2, 4, 5, 10, 20, 43, 86, 172, 215, 430, 860.
What is 860 in binary?
1101011100 (hexadecimal 35C, octal 1534).
What is the square root of 860?
About 29.3258, exactly 2√215.
What is 860 in Roman numerals?
DCCCLX.
Is 860 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 860?
860 is a happy number: repeatedly adding the squares of its digits reaches 1.