The number 266
266 is a composite number with 8 divisors. Its prime factorisation is 2 × 7 × 19. Divisors (8): 1, 2, 7, 14, 19, 38, 133, 266.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 266: a Harshad number: divisible by its digit sum 14.
- 2
266 is composite. Its prime factorisation is
- 3
The divisors add up to 480; without 266 itself that is 214, so 266 is deficient (214 is less than 266). Euler's totient φ(266) = 108 numbers up to 266 share no factor with it.
- 4
The digits of 266 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 29 steps to reach 1.
LaTeX source of the formulas on this page
\[ 266 = 2 \times 7 \times 19 \]
266 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 480 |
| Euler totient φ(n) | 108 |
| Square | 70756 |
| Cube | 18821096 |
| Square root | 16.309506 |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 29 |
| Scientific notation | 2.66 × |
266 in other forms
| Form | Value |
|---|---|
| In words | two hundred and sixty-six |
| Roman numerals | CCLXVI |
| Binary (base 2) | 100001010 |
| Octal (base 8) | 412 |
| Hexadecimal (base 16) | 10A |
| Base 3 | 100212 |
| As time | 266 seconds = 4 min 26 s |
Is 266 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (266 ÷ 2 = 133) | 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 | No (remainder 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | 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 | Yes (266 ÷ 7 = 38) | 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 2) | 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 | No (remainder 6) | 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 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 266 a prime number?
No. 266 = 2 × 7 × 19, so it is divisible by 2.
What are the factors of 266?
1, 2, 7, 14, 19, 38, 133, 266.
What is 266 in binary?
100001010 (hexadecimal 10A, octal 412).
What is the square root of 266?
About 16.3095.
What is 266 in Roman numerals?
CCLXVI.
Is 266 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 266?
266 is a Harshad number: divisible by its digit sum 14.