The number 20210
20210 is a composite number with 16 divisors. Its prime factorisation is 2 × 5 × 43 × 47. Divisors (16): 1, 2, 5, 10, 43, 47, 86, 94, 215, 235, 430, 470, 2021, 4042, 10105, 20210.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 20210: a Harshad number: divisible by its digit sum 5.
- 2
20210 is composite. Its prime factorisation is
- 3
The divisors add up to 38016; without 20210 itself that is 17806, so 20210 is deficient (17806 is less than 20210). Euler's totient φ(20210) = 7728 numbers up to 20210 share no factor with it.
- 4
The digits of 20210 add up to 5, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 136 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20210 = 2 \times 5 \times 43 \times 47 \]
20210 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 38016 |
| Euler totient φ(n) | 7728 |
| Square | 408444100 |
| Cube | 8254655261000 |
| Square root | 142.161880 |
| Digit sum / digital root | 5 / 5 |
| Collatz steps to 1 | 136 |
| Scientific notation | 2.021 × |
20210 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand two hundred and ten |
| Binary (base 2) | 100111011110010 |
| Octal (base 8) | 47362 |
| Hexadecimal (base 16) | 4EF2 |
| Base 3 | 1000201112 |
| As time | 20210 seconds = 5 h 36 min 50 s |
Is 20210 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (20210 ÷ 2 = 10105) | 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 | Yes (20210 ÷ 5 = 4042) | 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 1) | 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 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (20210 ÷ 10 = 2021) | 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 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20210 a prime number?
No. 20210 = 2 × 5 × 43 × 47, so it is divisible by 2.
What are the factors of 20210?
1, 2, 5, 10, 43, 47, 86, 94, 215, 235, 430, 470, 2021, 4042, 10105, 20210.
What is 20210 in binary?
100111011110010 (hexadecimal 4EF2, octal 47362).
What is the square root of 20210?
About 142.1619.
Is 20210 divisible by 3?
No. Its digits add up to 5, which is not a multiple of 3.
What is special about the number 20210?
20210 is a Harshad number: divisible by its digit sum 5.