The number 1213
1213 is the 198th prime number. Its only divisors are 1 and 1213.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1213: the 198th prime number.
- 2
1213 is prime, so its only factors are 1 and 1213. It is the 198th prime; the next prime is 1217 and the one before is 1201.
- 3
The divisors add up to 1214; without 1213 itself that is 1, so 1213 is deficient (1 is less than 1213). Euler's totient φ(1213) = 1212 numbers up to 1213 share no factor with it.
- 4
The digits of 1213 add up to 7, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 44 steps to reach 1.
1213 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 1214 |
| Euler totient φ(n) | 1212 |
| Square | 1471369 |
| Cube | 1784770597 |
| Square root | 34.828150 |
| Digit sum / digital root | 7 / 7 |
| Collatz steps to 1 | 44 |
| Scientific notation | 1.213 × |
1213 in other forms
| Form | Value |
|---|---|
| In words | one thousand two hundred and thirteen |
| Roman numerals | MCCXIII |
| Binary (base 2) | 10010111101 |
| Octal (base 8) | 2275 |
| Hexadecimal (base 16) | 4BD |
| Base 3 | 1122221 |
| As time | 1213 seconds = 20 min 13 s |
Is 1213 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 1) | 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 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 1) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 3) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 1213 a prime number?
Yes. 1213 is divisible only by 1 and itself.
What are the factors of 1213?
1, 1213.
What is 1213 in binary?
10010111101 (hexadecimal 4BD, octal 2275).
What is the square root of 1213?
About 34.8281.
What is 1213 in Roman numerals?
MCCXIII.
Is 1213 divisible by 3?
No. Its digits add up to 7, which is not a multiple of 3.
What is special about the number 1213?
1213 is the 198th prime number.