The number 12015
12015 is a composite number with 16 divisors. Its prime factorisation is × 5 × 89. Divisors (16): 1, 3, 5, 9, 15, 27, 45, 89, 135, 267, 445, 801, 1335, 2403, 4005, 12015.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 12015: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 9.
- 2
12015 is composite. Its prime factorisation is
- 3
The divisors add up to 21600; without 12015 itself that is 9585, so 12015 is deficient (9585 is less than 12015). Euler's totient φ(12015) = 6336 numbers up to 12015 share no factor with it.
- 4
The digits of 12015 add up to 9, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 94 steps to reach 1.
LaTeX source of the formulas on this page
\[ 12015 = 3^{3} \times 5 \times 89 \]12015 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 21600 |
| Euler totient φ(n) | 6336 |
| Square | 144360225 |
| Cube | 1734488103375 |
| Square root | 109.612955 (= 3√1335) |
| Digit sum / digital root | 9 / 9 |
| Collatz steps to 1 | 94 |
| Scientific notation | 1.2015 × |
12015 in other forms
| Form | Value |
|---|---|
| In words | twelve thousand and fifteen |
| Binary (base 2) | 10111011101111 |
| Octal (base 8) | 27357 |
| Hexadecimal (base 16) | 2EEF |
| Base 3 | 121111000 |
| As time | 12015 seconds = 3 h 20 min 15 s |
Is 12015 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 (12015 ÷ 3 = 4005) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (12015 ÷ 5 = 2403) | 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 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (12015 ÷ 9 = 1335) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 5) | 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 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 12015 a prime number?
No. 12015 = × 5 × 89, so it is divisible by 3.
What are the factors of 12015?
1, 3, 5, 9, 15, 27, 45, 89, 135, 267, 445, 801, 1335, 2403, 4005, 12015.
What is 12015 in binary?
10111011101111 (hexadecimal 2EEF, octal 27357).
What is the square root of 12015?
About 109.6130, exactly 3√1335.
Is 12015 divisible by 3?
Yes. Its digits add up to 9, a multiple of 3.
What is special about the number 12015?
12015 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 9.