The number 20940
20940 is a composite number with 24 divisors. Its prime factorisation is × 3 × 5 × 349. Divisors (24): 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60, 349, 698, 1047, 1396 … 20940.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 20940: a Harshad number: divisible by its digit sum 15.
- 2
20940 is composite. Its prime factorisation is
- 3
The divisors add up to 58800; without 20940 itself that is 37860, so 20940 is abundant (37860 is more than 20940). Euler's totient φ(20940) = 5568 numbers up to 20940 share no factor with it.
- 4
The digits of 20940 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 87 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20940 = 2^{2} \times 3 \times 5 \times 349 \]20940 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 58800 |
| Euler totient φ(n) | 5568 |
| Square | 438483600 |
| Cube | 9181846584000 |
| Square root | 144.706600 (= 2√5235) |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 87 |
| Scientific notation | 2.094 × |
20940 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand nine hundred and forty |
| Binary (base 2) | 101000111001100 |
| Octal (base 8) | 50714 |
| Hexadecimal (base 16) | 51CC |
| Base 3 | 1001201120 |
| As time | 20940 seconds = 5 h 49 min 0 s |
Is 20940 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (20940 ÷ 2 = 10470) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (20940 ÷ 3 = 6980) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (20940 ÷ 4 = 5235) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (20940 ÷ 5 = 4188) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (20940 ÷ 6 = 3490) | 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 4) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (20940 ÷ 10 = 2094) | 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 | Yes (20940 ÷ 12 = 1745) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20940 a prime number?
No. 20940 = × 3 × 5 × 349, so it is divisible by 2.
What are the factors of 20940?
1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60, 349, 698, 1047, 1396, 1745, 2094, 3490, 4188, 5235, 6980, 10470, 20940.
What is 20940 in binary?
101000111001100 (hexadecimal 51CC, octal 50714).
What is the square root of 20940?
About 144.7066, exactly 2√5235.
Is 20940 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 20940?
20940 is a Harshad number: divisible by its digit sum 15.