The number 21364
21364 is a composite number with 18 divisors. Its prime factorisation is × × 109. Divisors (18): 1, 2, 4, 7, 14, 28, 49, 98, 109, 196, 218, 436, 763, 1526, 3052, 5341 … 21364.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
21364 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
21364 is composite. Its prime factorisation is
- 3
The divisors add up to 43890; without 21364 itself that is 22526, so 21364 is abundant (22526 is more than 21364). Euler's totient φ(21364) = 9072 numbers up to 21364 share no factor with it.
- 4
The digits of 21364 add up to 16, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 149 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21364 = 2^{2} \times 7^{2} \times 109 \]21364 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 18 |
| Sum of divisors | 43890 |
| Euler totient φ(n) | 9072 |
| Square | 456420496 |
| Cube | 9750967476544 |
| Square root | 146.164291 (= 14√109) |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 149 |
| Scientific notation | 2.1364 × |
21364 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand three hundred and sixty-four |
| Binary (base 2) | 101001101110100 |
| Octal (base 8) | 51564 |
| Hexadecimal (base 16) | 5374 |
| Base 3 | 1002022021 |
| As time | 21364 seconds = 5 h 56 min 4 s |
Is 21364 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (21364 ÷ 2 = 10682) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (21364 ÷ 4 = 5341) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 4) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (21364 ÷ 7 = 3052) | 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 4) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 4) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 2) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 21364 a prime number?
No. 21364 = × × 109, so it is divisible by 2.
What are the factors of 21364?
1, 2, 4, 7, 14, 28, 49, 98, 109, 196, 218, 436, 763, 1526, 3052, 5341, 10682, 21364.
What is 21364 in binary?
101001101110100 (hexadecimal 5374, octal 51564).
What is the square root of 21364?
About 146.1643, exactly 14√109.
Is 21364 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 21364?
It is a composite number with 18 divisors.