The number 21373
21373 is a composite number with 8 divisors. Its prime factorisation is 11 × 29 × 67. Divisors (8): 1, 11, 29, 67, 319, 737, 1943, 21373.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
21373 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
21373 is composite. Its prime factorisation is
- 3
The divisors add up to 24480; without 21373 itself that is 3107, so 21373 is deficient (3107 is less than 21373). Euler's totient φ(21373) = 18480 numbers up to 21373 share no factor with it.
- 4
The digits of 21373 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 48 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21373 = 11 \times 29 \times 67 \]
21373 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 24480 |
| Euler totient φ(n) | 18480 |
| Square | 456805129 |
| Cube | 9763296022117 |
| Square root | 146.195075 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 48 |
| Scientific notation | 2.1373 × |
21373 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand three hundred and seventy-three |
| Binary (base 2) | 101001101111101 |
| Octal (base 8) | 51575 |
| Hexadecimal (base 16) | 537D |
| Base 3 | 1002022121 |
| As time | 21373 seconds = 5 h 56 min 13 s |
Is 21373 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 | No (remainder 1) | 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 1) | 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 5) | 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 3) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (21373 ÷ 11 = 1943) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 21373 a prime number?
No. 21373 = 11 × 29 × 67, so it is divisible by 11.
What are the factors of 21373?
1, 11, 29, 67, 319, 737, 1943, 21373.
What is 21373 in binary?
101001101111101 (hexadecimal 537D, octal 51575).
What is the square root of 21373?
About 146.1951.
Is 21373 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 21373?
It is a composite number with 8 divisors.