The number 13521
13521 is a composite number with 4 divisors. Its prime factorisation is 3 × 4507. Divisors (4): 1, 3, 4507, 13521.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 13521: a semiprime: 3 × 4507, the product of two primes.
- 2
13521 is composite. Its prime factorisation is
- 3
The divisors add up to 18032; without 13521 itself that is 4511, so 13521 is deficient (4511 is less than 13521). Euler's totient φ(13521) = 9012 numbers up to 13521 share no factor with it.
- 4
The digits of 13521 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 89 steps to reach 1.
LaTeX source of the formulas on this page
\[ 13521 = 3 \times 4507 \]
13521 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 18032 |
| Euler totient φ(n) | 9012 |
| Square | 182817441 |
| Cube | 2471874619761 |
| Square root | 116.279835 |
| Digit sum / digital root | 12 / 3 |
| Collatz steps to 1 | 89 |
| Scientific notation | 1.3521 × |
13521 in other forms
| Form | Value |
|---|---|
| In words | thirteen thousand five hundred and twenty-one |
| Binary (base 2) | 11010011010001 |
| Octal (base 8) | 32321 |
| Hexadecimal (base 16) | 34D1 |
| Base 3 | 200112210 |
| As time | 13521 seconds = 3 h 45 min 21 s |
Is 13521 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 (13521 ÷ 3 = 4507) | 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 1) | 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 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 2) | 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 13521 a prime number?
No. 13521 = 3 × 4507, so it is divisible by 3.
What are the factors of 13521?
1, 3, 4507, 13521.
What is 13521 in binary?
11010011010001 (hexadecimal 34D1, octal 32321).
What is the square root of 13521?
About 116.2798.
Is 13521 divisible by 3?
Yes. Its digits add up to 12, a multiple of 3.
What is special about the number 13521?
13521 is a semiprime: 3 × 4507, the product of two primes.