The number 17421
17421 is a composite number with 4 divisors. Its prime factorisation is 3 × 5807. Divisors (4): 1, 3, 5807, 17421.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 17421: a semiprime: 3 × 5807, the product of two primes.
- 2
17421 is composite. Its prime factorisation is
- 3
The divisors add up to 23232; without 17421 itself that is 5811, so 17421 is deficient (5811 is less than 17421). Euler's totient φ(17421) = 11612 numbers up to 17421 share no factor with it.
- 4
The digits of 17421 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 141 steps to reach 1.
LaTeX source of the formulas on this page
\[ 17421 = 3 \times 5807 \]
17421 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 23232 |
| Euler totient φ(n) | 11612 |
| Square | 303491241 |
| Cube | 5287120909461 |
| Square root | 131.988636 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 141 |
| Scientific notation | 1.7421 × |
17421 in other forms
| Form | Value |
|---|---|
| In words | seventeen thousand four hundred and twenty-one |
| Binary (base 2) | 100010000001101 |
| Octal (base 8) | 42015 |
| Hexadecimal (base 16) | 440D |
| Base 3 | 212220020 |
| As time | 17421 seconds = 4 h 50 min 21 s |
Is 17421 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 (17421 ÷ 3 = 5807) | 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 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 6) | 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 8) | 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 17421 a prime number?
No. 17421 = 3 × 5807, so it is divisible by 3.
What are the factors of 17421?
1, 3, 5807, 17421.
What is 17421 in binary?
100010000001101 (hexadecimal 440D, octal 42015).
What is the square root of 17421?
About 131.9886.
Is 17421 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 17421?
17421 is a semiprime: 3 × 5807, the product of two primes.