The number 1187
1187 is the 195th prime number. Its only divisors are 1 and 1187.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1187: the 195th prime number.
- 2
1187 is prime, so its only factors are 1 and 1187. It is the 195th prime; the next prime is 1193 and the one before is 1181.
- 3
The divisors add up to 1188; without 1187 itself that is 1, so 1187 is deficient (1 is less than 1187). Euler's totient φ(1187) = 1186 numbers up to 1187 share no factor with it.
- 4
The digits of 1187 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 75 steps to reach 1.
1187 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 1188 |
| Euler totient φ(n) | 1186 |
| Square | 1408969 |
| Cube | 1672446203 |
| Square root | 34.452866 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 75 |
| Scientific notation | 1.187 × |
1187 in other forms
| Form | Value |
|---|---|
| In words | one thousand one hundred and eighty-seven |
| Roman numerals | MCLXXXVII |
| Binary (base 2) | 10010100011 |
| Octal (base 8) | 2243 |
| Hexadecimal (base 16) | 4A3 |
| Base 3 | 1121222 |
| As time | 1187 seconds = 19 min 47 s |
Is 1187 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 | No (remainder 2) | 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 | No (remainder 2) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 4) | 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 8) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 7) | 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 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 1187 a prime number?
Yes. 1187 is divisible only by 1 and itself.
What are the factors of 1187?
1, 1187.
What is 1187 in binary?
10010100011 (hexadecimal 4A3, octal 2243).
What is the square root of 1187?
About 34.4529.
What is 1187 in Roman numerals?
MCLXXXVII.
Is 1187 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 1187?
1187 is the 195th prime number.