The number 20188
20188 is a composite number with 18 divisors. Its prime factorisation is × × 103. Divisors (18): 1, 2, 4, 7, 14, 28, 49, 98, 103, 196, 206, 412, 721, 1442, 2884, 5047 … 20188.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 20188: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
20188 is composite. Its prime factorisation is
- 3
The divisors add up to 41496; without 20188 itself that is 21308, so 20188 is abundant (21308 is more than 20188). Euler's totient φ(20188) = 8568 numbers up to 20188 share no factor with it.
- 4
The digits of 20188 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 136 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20188 = 2^{2} \times 7^{2} \times 103 \]20188 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 18 |
| Sum of divisors | 41496 |
| Euler totient φ(n) | 8568 |
| Square | 407555344 |
| Cube | 8227727284672 |
| Square root | 142.084482 (= 14√103) |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 136 |
| Scientific notation | 2.0188 × |
20188 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand one hundred and eighty-eight |
| Binary (base 2) | 100111011011100 |
| Octal (base 8) | 47334 |
| Hexadecimal (base 16) | 4EDC |
| Base 3 | 1000200201 |
| As time | 20188 seconds = 5 h 36 min 28 s |
Is 20188 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (20188 ÷ 2 = 10094) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (20188 ÷ 4 = 5047) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (20188 ÷ 7 = 2884) | 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 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 8) | 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 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20188 a prime number?
No. 20188 = × × 103, so it is divisible by 2.
What are the factors of 20188?
1, 2, 4, 7, 14, 28, 49, 98, 103, 196, 206, 412, 721, 1442, 2884, 5047, 10094, 20188.
What is 20188 in binary?
100111011011100 (hexadecimal 4EDC, octal 47334).
What is the square root of 20188?
About 142.0845, exactly 14√103.
Is 20188 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 20188?
20188 is a happy number: repeatedly adding the squares of its digits reaches 1.