The number 1217
1217 is the 199th prime number. Its only divisors are 1 and 1217.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1217: the 199th prime number.
- 2
1217 is prime, so its only factors are 1 and 1217. It is the 199th prime; the next prime is 1223 and the one before is 1213.
- 3
The divisors add up to 1218; without 1217 itself that is 1, so 1217 is deficient (1 is less than 1217). Euler's totient φ(1217) = 1216 numbers up to 1217 share no factor with it.
- 4
The digits of 1217 add up to 11, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 132 steps to reach 1.
1217 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 1218 |
| Euler totient φ(n) | 1216 |
| Square | 1481089 |
| Cube | 1802485313 |
| Square root | 34.885527 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 132 |
| Scientific notation | 1.217 × |
1217 in other forms
| Form | Value |
|---|---|
| In words | one thousand two hundred and seventeen |
| Roman numerals | MCCXVII |
| Binary (base 2) | 10011000001 |
| Octal (base 8) | 2301 |
| Hexadecimal (base 16) | 4C1 |
| Base 3 | 1200002 |
| As time | 1217 seconds = 20 min 17 s |
Is 1217 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 1) | 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 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | 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 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 1217 a prime number?
Yes. 1217 is divisible only by 1 and itself.
What are the factors of 1217?
1, 1217.
What is 1217 in binary?
10011000001 (hexadecimal 4C1, octal 2301).
What is the square root of 1217?
About 34.8855.
What is 1217 in Roman numerals?
MCCXVII.
Is 1217 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 1217?
1217 is the 199th prime number.