The number 28401
28401 is a composite number with 4 divisors. Its prime factorisation is 3 × 9467. Divisors (4): 1, 3, 9467, 28401.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 28401: a semiprime: 3 × 9467, the product of two primes.
- 2
28401 is composite. Its prime factorisation is
- 3
The divisors add up to 37872; without 28401 itself that is 9471, so 28401 is deficient (9471 is less than 28401). Euler's totient φ(28401) = 18932 numbers up to 28401 share no factor with it.
- 4
The digits of 28401 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 59 steps to reach 1.
LaTeX source of the formulas on this page
\[ 28401 = 3 \times 9467 \]
28401 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 37872 |
| Euler totient φ(n) | 18932 |
| Square | 806616801 |
| Cube | 22908723765201 |
| Square root | 168.525962 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 59 |
| Scientific notation | 2.8401 × |
28401 in other forms
| Form | Value |
|---|---|
| In words | twenty-eight thousand four hundred and one |
| Binary (base 2) | 110111011110001 |
| Octal (base 8) | 67361 |
| Hexadecimal (base 16) | 6EF1 |
| Base 3 | 1102221220 |
| As time | 28401 seconds = 7 h 53 min 21 s |
Is 28401 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 (28401 ÷ 3 = 9467) | 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 2) | 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 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 10) | 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 28401 a prime number?
No. 28401 = 3 × 9467, so it is divisible by 3.
What are the factors of 28401?
1, 3, 9467, 28401.
What is 28401 in binary?
110111011110001 (hexadecimal 6EF1, octal 67361).
What is the square root of 28401?
About 168.5260.
Is 28401 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 28401?
28401 is a semiprime: 3 × 9467, the product of two primes.