The number 20172
20172 is a composite number with 18 divisors. Its prime factorisation is × 3 × . Divisors (18): 1, 2, 3, 4, 6, 12, 41, 82, 123, 164, 246, 492, 1681, 3362, 5043, 6724 … 20172.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 20172: a Harshad number: divisible by its digit sum 12.
- 2
20172 is composite. Its prime factorisation is
- 3
The divisors add up to 48244; without 20172 itself that is 28072, so 20172 is abundant (28072 is more than 20172). Euler's totient φ(20172) = 6560 numbers up to 20172 share no factor with it.
- 4
The digits of 20172 add up to 12, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 43 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20172 = 2^{2} \times 3 \times 41^{2} \]20172 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 18 |
| Sum of divisors | 48244 |
| Euler totient φ(n) | 6560 |
| Square | 406909584 |
| Cube | 8208180128448 |
| Square root | 142.028166 (= 82√3) |
| Digit sum / digital root | 12 / 3 |
| Collatz steps to 1 | 43 |
| Scientific notation | 2.0172 × |
20172 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand one hundred and seventy-two |
| Binary (base 2) | 100111011001100 |
| Octal (base 8) | 47314 |
| Hexadecimal (base 16) | 4ECC |
| Base 3 | 1000200010 |
| As time | 20172 seconds = 5 h 36 min 12 s |
Is 20172 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (20172 ÷ 2 = 10086) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (20172 ÷ 3 = 6724) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (20172 ÷ 4 = 5043) | 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 | Yes (20172 ÷ 6 = 3362) | 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 4) | 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 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (20172 ÷ 12 = 1681) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20172 a prime number?
No. 20172 = × 3 × , so it is divisible by 2.
What are the factors of 20172?
1, 2, 3, 4, 6, 12, 41, 82, 123, 164, 246, 492, 1681, 3362, 5043, 6724, 10086, 20172.
What is 20172 in binary?
100111011001100 (hexadecimal 4ECC, octal 47314).
What is the square root of 20172?
About 142.0282, exactly 82√3.
Is 20172 divisible by 3?
Yes. Its digits add up to 12, a multiple of 3.
What is special about the number 20172?
20172 is a Harshad number: divisible by its digit sum 12.