The number 13215
13215 is a composite number with 8 divisors. Its prime factorisation is 3 × 5 × 881. Divisors (8): 1, 3, 5, 15, 881, 2643, 4405, 13215.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
13215 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
13215 is composite. Its prime factorisation is
- 3
The divisors add up to 21168; without 13215 itself that is 7953, so 13215 is deficient (7953 is less than 13215). Euler's totient φ(13215) = 7040 numbers up to 13215 share no factor with it.
- 4
The digits of 13215 add up to 12, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 169 steps to reach 1.
LaTeX source of the formulas on this page
\[ 13215 = 3 \times 5 \times 881 \]
13215 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 21168 |
| Euler totient φ(n) | 7040 |
| Square | 174636225 |
| Cube | 2307817713375 |
| Square root | 114.956514 |
| Digit sum / digital root | 12 / 3 |
| Collatz steps to 1 | 169 |
| Scientific notation | 1.3215 × |
13215 in other forms
| Form | Value |
|---|---|
| In words | thirteen thousand two hundred and fifteen |
| Binary (base 2) | 11001110011111 |
| Octal (base 8) | 31637 |
| Hexadecimal (base 16) | 339F |
| Base 3 | 200010110 |
| As time | 13215 seconds = 3 h 40 min 15 s |
Is 13215 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 (13215 ÷ 3 = 4405) | 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 (13215 ÷ 5 = 2643) | 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 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 7) | 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 5) | 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 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 13215 a prime number?
No. 13215 = 3 × 5 × 881, so it is divisible by 3.
What are the factors of 13215?
1, 3, 5, 15, 881, 2643, 4405, 13215.
What is 13215 in binary?
11001110011111 (hexadecimal 339F, octal 31637).
What is the square root of 13215?
About 114.9565.
Is 13215 divisible by 3?
Yes. Its digits add up to 12, a multiple of 3.
What is special about the number 13215?
It is a composite number with 8 divisors.