The number 21273
21273 is a composite number with 8 divisors. Its prime factorisation is 3 × 7 × 1013. Divisors (8): 1, 3, 7, 21, 1013, 3039, 7091, 21273.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
21273 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
21273 is composite. Its prime factorisation is
- 3
The divisors add up to 32448; without 21273 itself that is 11175, so 21273 is deficient (11175 is less than 21273). Euler's totient φ(21273) = 12144 numbers up to 21273 share no factor with it.
- 4
The digits of 21273 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 56 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21273 = 3 \times 7 \times 1013 \]
21273 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 32448 |
| Euler totient φ(n) | 12144 |
| Square | 452540529 |
| Cube | 9626894673417 |
| Square root | 145.852665 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 56 |
| Scientific notation | 2.1273 × |
21273 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand two hundred and seventy-three |
| Binary (base 2) | 101001100011001 |
| Octal (base 8) | 51431 |
| Hexadecimal (base 16) | 5319 |
| Base 3 | 1002011220 |
| As time | 21273 seconds = 5 h 54 min 33 s |
Is 21273 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 (21273 ÷ 3 = 7091) | 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 3) | 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 | Yes (21273 ÷ 7 = 3039) | 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 3) | 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 21273 a prime number?
No. 21273 = 3 × 7 × 1013, so it is divisible by 3.
What are the factors of 21273?
1, 3, 7, 21, 1013, 3039, 7091, 21273.
What is 21273 in binary?
101001100011001 (hexadecimal 5319, octal 51431).
What is the square root of 21273?
About 145.8527.
Is 21273 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 21273?
It is a composite number with 8 divisors.