The number 170
170 is a composite number with 8 divisors. Its prime factorisation is 2 × 5 × 17. Divisors (8): 1, 2, 5, 10, 17, 34, 85, 170.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
170 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
170 is composite. Its prime factorisation is
- 3
The divisors add up to 324; without 170 itself that is 154, so 170 is deficient (154 is less than 170). Euler's totient φ(170) = 64 numbers up to 170 share no factor with it.
- 4
The digits of 170 add up to 8, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 10 steps to reach 1.
LaTeX source of the formulas on this page
\[ 170 = 2 \times 5 \times 17 \]
170 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 324 |
| Euler totient φ(n) | 64 |
| Square | 28900 |
| Cube | 4913000 |
| Square root | 13.038405 |
| Digit sum / digital root | 8 / 8 |
| Collatz steps to 1 | 10 |
| Scientific notation | 1.7 × |
170 in other forms
| Form | Value |
|---|---|
| In words | one hundred and seventy |
| Roman numerals | CLXX |
| Binary (base 2) | 10101010 |
| Octal (base 8) | 252 |
| Hexadecimal (base 16) | AA |
| Base 3 | 20022 |
| As time | 170 seconds = 2 min 50 s |
Is 170 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (170 ÷ 2 = 85) | 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 | Yes (170 ÷ 5 = 34) | 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 8) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (170 ÷ 10 = 17) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 5) | 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 170 a prime number?
No. 170 = 2 × 5 × 17, so it is divisible by 2.
What are the factors of 170?
1, 2, 5, 10, 17, 34, 85, 170.
What is 170 in binary?
10101010 (hexadecimal AA, octal 252).
What is the square root of 170?
About 13.0384.
What is 170 in Roman numerals?
CLXX.
Is 170 divisible by 3?
No. Its digits add up to 8, which is not a multiple of 3.
What is special about the number 170?
It is a composite number with 8 divisors.