The number 38421
38421 is a composite number with 8 divisors. Its prime factorisation is × 1423. Divisors (8): 1, 3, 9, 27, 1423, 4269, 12807, 38421.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 38421: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
38421 is composite. Its prime factorisation is
- 3
The divisors add up to 56960; without 38421 itself that is 18539, so 38421 is deficient (18539 is less than 38421). Euler's totient φ(38421) = 25596 numbers up to 38421 share no factor with it.
- 4
The digits of 38421 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 168 steps to reach 1.
LaTeX source of the formulas on this page
\[ 38421 = 3^{3} \times 1423 \]38421 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 56960 |
| Euler totient φ(n) | 25596 |
| Square | 1476173241 |
| Cube | 56716052092461 |
| Square root | 196.012755 (= 3√4269) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 168 |
| Scientific notation | 3.8421 × |
38421 in other forms
| Form | Value |
|---|---|
| In words | thirty-eight thousand four hundred and twenty-one |
| Binary (base 2) | 1001011000010101 |
| Octal (base 8) | 113025 |
| Hexadecimal (base 16) | 9615 |
| Base 3 | 1221201000 |
| As time | 38421 seconds = 10 h 40 min 21 s |
Is 38421 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 (38421 ÷ 3 = 12807) | 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 | Yes (38421 ÷ 9 = 4269) | 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 9) | 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 38421 a prime number?
No. 38421 = × 1423, so it is divisible by 3.
What are the factors of 38421?
1, 3, 9, 27, 1423, 4269, 12807, 38421.
What is 38421 in binary?
1001011000010101 (hexadecimal 9615, octal 113025).
What is the square root of 38421?
About 196.0128, exactly 3√4269.
Is 38421 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 38421?
38421 is a happy number: repeatedly adding the squares of its digits reaches 1.