The number 2729
2729 is a twin prime (2729 and 2731 are both prime) and the 398th prime number. Its only divisors are 1 and 2729.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 2729: a twin prime (2729 and 2731 are both prime); the 398th prime number.
- 2
2729 is prime, so its only factors are 1 and 2729. It is the 398th prime; the next prime is 2731 and the one before is 2719.
- 3
The divisors add up to 2730; without 2729 itself that is 1, so 2729 is deficient (1 is less than 2729). Euler's totient φ(2729) = 2728 numbers up to 2729 share no factor with it.
- 4
The digits of 2729 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 159 steps to reach 1.
2729 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 2730 |
| Euler totient φ(n) | 2728 |
| Square | 7447441 |
| Cube | 20324066489 |
| Square root | 52.239832 |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 159 |
| Scientific notation | 2.729 × |
2729 in other forms
| Form | Value |
|---|---|
| In words | two thousand seven hundred and twenty-nine |
| Roman numerals | MMDCCXXIX |
| Binary (base 2) | 101010101001 |
| Octal (base 8) | 5251 |
| Hexadecimal (base 16) | AA9 |
| Base 3 | 10202002 |
| As time | 2729 seconds = 45 min 29 s |
Is 2729 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 4) | 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 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 1) | 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 2729 a prime number?
Yes. 2729 is divisible only by 1 and itself.
What are the factors of 2729?
1, 2729.
What is 2729 in binary?
101010101001 (hexadecimal AA9, octal 5251).
What is the square root of 2729?
About 52.2398.
What is 2729 in Roman numerals?
MMDCCXXIX.
Is 2729 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 2729?
2729 is a twin prime (2729 and 2731 are both prime); the 398th prime number.