The number 20874
20874 is a composite number with 24 divisors. Its prime factorisation is 2 × 3 × × 71. Divisors (24): 1, 2, 3, 6, 7, 14, 21, 42, 49, 71, 98, 142, 147, 213, 294, 426 … 20874.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 20874: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 21.
- 2
20874 is composite. Its prime factorisation is
- 3
The divisors add up to 49248; without 20874 itself that is 28374, so 20874 is abundant (28374 is more than 20874). Euler's totient φ(20874) = 5880 numbers up to 20874 share no factor with it.
- 4
The digits of 20874 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 56 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20874 = 2 \times 3 \times 7^{2} \times 71 \]20874 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 49248 |
| Euler totient φ(n) | 5880 |
| Square | 435723876 |
| Cube | 9095300187624 |
| Square root | 144.478372 (= 7√426) |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 56 |
| Scientific notation | 2.0874 × |
20874 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand eight hundred and seventy-four |
| Binary (base 2) | 101000110001010 |
| Octal (base 8) | 50612 |
| Hexadecimal (base 16) | 518A |
| Base 3 | 1001122010 |
| As time | 20874 seconds = 5 h 47 min 54 s |
Is 20874 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (20874 ÷ 2 = 10437) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (20874 ÷ 3 = 6958) | 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 | Yes (20874 ÷ 6 = 3479) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (20874 ÷ 7 = 2982) | 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | 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 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 6) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20874 a prime number?
No. 20874 = 2 × 3 × × 71, so it is divisible by 2.
What are the factors of 20874?
1, 2, 3, 6, 7, 14, 21, 42, 49, 71, 98, 142, 147, 213, 294, 426, 497, 994, 1491, 2982, 3479, 6958, 10437, 20874.
What is 20874 in binary?
101000110001010 (hexadecimal 518A, octal 50612).
What is the square root of 20874?
About 144.4784, exactly 7√426.
Is 20874 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 20874?
20874 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 21.