The number 21374
21374 is a composite number with 4 divisors. Its prime factorisation is 2 × 10687. Divisors (4): 1, 2, 10687, 21374.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 21374: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 2 × 10687, the product of two primes.
- 2
21374 is composite. Its prime factorisation is
- 3
The divisors add up to 32064; without 21374 itself that is 10690, so 21374 is deficient (10690 is less than 21374). Euler's totient φ(21374) = 10686 numbers up to 21374 share no factor with it.
- 4
The digits of 21374 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 100 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21374 = 2 \times 10687 \]
21374 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 32064 |
| Euler totient φ(n) | 10686 |
| Square | 456847876 |
| Cube | 9764666501624 |
| Square root | 146.198495 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 100 |
| Scientific notation | 2.1374 × |
21374 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand three hundred and seventy-four |
| Binary (base 2) | 101001101111110 |
| Octal (base 8) | 51576 |
| Hexadecimal (base 16) | 537E |
| Base 3 | 1002022122 |
| As time | 21374 seconds = 5 h 56 min 14 s |
Is 21374 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (21374 ÷ 2 = 10687) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 2) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 2) | 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 2) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | 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 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 8) | 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 1) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 21374 a prime number?
No. 21374 = 2 × 10687, so it is divisible by 2.
What are the factors of 21374?
1, 2, 10687, 21374.
What is 21374 in binary?
101001101111110 (hexadecimal 537E, octal 51576).
What is the square root of 21374?
About 146.1985.
Is 21374 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 21374?
21374 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 2 × 10687, the product of two primes.