The number 21376
21376 is a composite number with 16 divisors. Its prime factorisation is × 167. Divisors (16): 1, 2, 4, 8, 16, 32, 64, 128, 167, 334, 668, 1336, 2672, 5344, 10688, 21376.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
21376 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
21376 is composite. Its prime factorisation is
- 3
The divisors add up to 42840; without 21376 itself that is 21464, so 21376 is abundant (21464 is more than 21376). Euler's totient φ(21376) = 10624 numbers up to 21376 share no factor with it.
- 4
The digits of 21376 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 74 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21376 = 2^{7} \times 167 \]21376 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 42840 |
| Euler totient φ(n) | 10624 |
| Square | 456933376 |
| Cube | 9767407845376 |
| Square root | 146.205335 (= 8√334) |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 74 |
| Scientific notation | 2.1376 × |
21376 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand three hundred and seventy-six |
| Binary (base 2) | 101001110000000 |
| Octal (base 8) | 51600 |
| Hexadecimal (base 16) | 5380 |
| Base 3 | 1002022201 |
| As time | 21376 seconds = 5 h 56 min 16 s |
Is 21376 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (21376 ÷ 2 = 10688) | 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 (21376 ÷ 4 = 5344) | 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 4) | 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 | Yes (21376 ÷ 8 = 2672) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 6) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 3) | 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 21376 a prime number?
No. 21376 = × 167, so it is divisible by 2.
What are the factors of 21376?
1, 2, 4, 8, 16, 32, 64, 128, 167, 334, 668, 1336, 2672, 5344, 10688, 21376.
What is 21376 in binary?
101001110000000 (hexadecimal 5380, octal 51600).
What is the square root of 21376?
About 146.2053, exactly 8√334.
Is 21376 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 21376?
It is a composite number with 16 divisors.