The number 195
195 is a binary palindrome (11000011). Its prime factorisation is 3 × 5 × 13. Divisors (8): 1, 3, 5, 13, 15, 39, 65, 195.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 195: a binary palindrome (11000011); a Harshad number: divisible by its digit sum 15.
- 2
195 is composite. Its prime factorisation is
- 3
The divisors add up to 336; without 195 itself that is 141, so 195 is deficient (141 is less than 195). Euler's totient φ(195) = 96 numbers up to 195 share no factor with it.
- 4
The digits of 195 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 119 steps to reach 1.
LaTeX source of the formulas on this page
\[ 195 = 3 \times 5 \times 13 \]
195 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 336 |
| Euler totient φ(n) | 96 |
| Square | 38025 |
| Cube | 7414875 |
| Square root | 13.964240 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 119 |
| Scientific notation | 1.95 × |
195 in other forms
| Form | Value |
|---|---|
| In words | one hundred and ninety-five |
| Roman numerals | CXCV |
| Binary (base 2) | 11000011 |
| Octal (base 8) | 303 |
| Hexadecimal (base 16) | C3 |
| Base 3 | 21020 |
| As time | 195 seconds = 3 min 15 s |
Is 195 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (195 ÷ 3 = 65) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (195 ÷ 5 = 39) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | 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 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 5) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 195 a prime number?
No. 195 = 3 × 5 × 13, so it is divisible by 3.
What are the factors of 195?
1, 3, 5, 13, 15, 39, 65, 195.
What is 195 in binary?
11000011 (hexadecimal C3, octal 303).
What is the square root of 195?
About 13.9642.
What is 195 in Roman numerals?
CXCV.
Is 195 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 195?
195 is a binary palindrome (11000011); a Harshad number: divisible by its digit sum 15.