The number 27129
27129 is a composite number with 4 divisors. Its prime factorisation is 3 × 9043. Divisors (4): 1, 3, 9043, 27129.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 27129: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 3 × 9043, the product of two primes.
- 2
27129 is composite. Its prime factorisation is
- 3
The divisors add up to 36176; without 27129 itself that is 9047, so 27129 is deficient (9047 is less than 27129). Euler's totient φ(27129) = 18084 numbers up to 27129 share no factor with it.
- 4
The digits of 27129 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 77 steps to reach 1.
LaTeX source of the formulas on this page
\[ 27129 = 3 \times 9043 \]
27129 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 36176 |
| Euler totient φ(n) | 18084 |
| Square | 735982641 |
| Cube | 19966473067689 |
| Square root | 164.708834 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 77 |
| Scientific notation | 2.7129 × |
27129 in other forms
| Form | Value |
|---|---|
| In words | twenty-seven thousand one hundred and twenty-nine |
| Binary (base 2) | 110100111111001 |
| Octal (base 8) | 64771 |
| Hexadecimal (base 16) | 69F9 |
| Base 3 | 1101012210 |
| As time | 27129 seconds = 7 h 32 min 9 s |
Is 27129 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 | Yes (27129 ÷ 3 = 9043) | 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 3) | 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | 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 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 27129 a prime number?
No. 27129 = 3 × 9043, so it is divisible by 3.
What are the factors of 27129?
1, 3, 9043, 27129.
What is 27129 in binary?
110100111111001 (hexadecimal 69F9, octal 64771).
What is the square root of 27129?
About 164.7088.
Is 27129 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 27129?
27129 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 3 × 9043, the product of two primes.