The number 829
829 is a twin prime (827 and 829 are both prime) and the 145th prime number. Its only divisors are 1 and 829.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 829: a twin prime (827 and 829 are both prime); the 145th prime number.
- 2
829 is prime, so its only factors are 1 and 829. It is the 145th prime; the next prime is 839 and the one before is 827.
- 3
The divisors add up to 830; without 829 itself that is 1, so 829 is deficient (1 is less than 829). Euler's totient φ(829) = 828 numbers up to 829 share no factor with it.
- 4
The digits of 829 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 90 steps to reach 1.
829 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 830 |
| Euler totient φ(n) | 828 |
| Square | 687241 |
| Cube | 569722789 |
| Square root | 28.792360 |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 90 |
| Scientific notation | 8.29 × |
829 in other forms
| Form | Value |
|---|---|
| In words | eight hundred and twenty-nine |
| Roman numerals | DCCCXXIX |
| Binary (base 2) | 1100111101 |
| Octal (base 8) | 1475 |
| Hexadecimal (base 16) | 33D |
| Base 3 | 1010201 |
| As time | 829 seconds = 13 min 49 s |
Is 829 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 4) | 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 3) | 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 1) | 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 4) | 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 829 a prime number?
Yes. 829 is divisible only by 1 and itself.
What are the factors of 829?
1, 829.
What is 829 in binary?
1100111101 (hexadecimal 33D, octal 1475).
What is the square root of 829?
About 28.7924.
What is 829 in Roman numerals?
DCCCXXIX.
Is 829 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 829?
829 is a twin prime (827 and 829 are both prime); the 145th prime number.