The number 13445
13445 is a composite number with 4 divisors. Its prime factorisation is 5 × 2689. Divisors (4): 1, 5, 2689, 13445.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 13445: a semiprime: 5 × 2689, the product of two primes.
- 2
13445 is composite. Its prime factorisation is
- 3
The divisors add up to 16140; without 13445 itself that is 2695, so 13445 is deficient (2695 is less than 13445). Euler's totient φ(13445) = 10752 numbers up to 13445 share no factor with it.
- 4
The digits of 13445 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 45 steps to reach 1.
LaTeX source of the formulas on this page
\[ 13445 = 5 \times 2689 \]
13445 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 16140 |
| Euler totient φ(n) | 10752 |
| Square | 180768025 |
| Cube | 2430426096125 |
| Square root | 115.952577 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 45 |
| Scientific notation | 1.3445 × |
13445 in other forms
| Form | Value |
|---|---|
| In words | thirteen thousand four hundred and forty-five |
| Binary (base 2) | 11010010000101 |
| Octal (base 8) | 32205 |
| Hexadecimal (base 16) | 3485 |
| Base 3 | 200102222 |
| As time | 13445 seconds = 3 h 44 min 5 s |
Is 13445 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 2) | 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 | Yes (13445 ÷ 5 = 2689) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 5) | 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 8) | 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 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 13445 a prime number?
No. 13445 = 5 × 2689, so it is divisible by 5.
What are the factors of 13445?
1, 5, 2689, 13445.
What is 13445 in binary?
11010010000101 (hexadecimal 3485, octal 32205).
What is the square root of 13445?
About 115.9526.
Is 13445 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 13445?
13445 is a semiprime: 5 × 2689, the product of two primes.