The number 20837
20837 is a composite number with 4 divisors. Its prime factorisation is 67 × 311. Divisors (4): 1, 67, 311, 20837.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 20837: a semiprime: 67 × 311, the product of two primes.
- 2
20837 is composite. Its prime factorisation is
- 3
The divisors add up to 21216; without 20837 itself that is 379, so 20837 is deficient (379 is less than 20837). Euler's totient φ(20837) = 20460 numbers up to 20837 share no factor with it.
- 4
The digits of 20837 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 43 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20837 = 67 \times 311 \]
20837 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 21216 |
| Euler totient φ(n) | 20460 |
| Square | 434180569 |
| Cube | 9047020516253 |
| Square root | 144.350268 |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 43 |
| Scientific notation | 2.0837 × |
20837 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand eight hundred and thirty-seven |
| Binary (base 2) | 101000101100101 |
| Octal (base 8) | 50545 |
| Hexadecimal (base 16) | 5165 |
| Base 3 | 1001120202 |
| As time | 20837 seconds = 5 h 47 min 17 s |
Is 20837 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 2) | 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 2) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 5) | 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 | No (remainder 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 7) | 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 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20837 a prime number?
No. 20837 = 67 × 311, so it is divisible by 67.
What are the factors of 20837?
1, 67, 311, 20837.
What is 20837 in binary?
101000101100101 (hexadecimal 5165, octal 50545).
What is the square root of 20837?
About 144.3503.
Is 20837 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 20837?
20837 is a semiprime: 67 × 311, the product of two primes.