The number 20025
20025 is a binary palindrome (100111000111001). Its prime factorisation is × × 89. Divisors (18): 1, 3, 5, 9, 15, 25, 45, 75, 89, 225, 267, 445, 801, 1335, 2225, 4005 … 20025.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 20025: a binary palindrome (100111000111001); a Harshad number: divisible by its digit sum 9.
- 2
20025 is composite. Its prime factorisation is
- 3
The divisors add up to 36270; without 20025 itself that is 16245, so 20025 is deficient (16245 is less than 20025). Euler's totient φ(20025) = 10560 numbers up to 20025 share no factor with it.
- 4
The digits of 20025 add up to 9, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 136 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20025 = 3^{2} \times 5^{2} \times 89 \]20025 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 18 |
| Sum of divisors | 36270 |
| Euler totient φ(n) | 10560 |
| Square | 401000625 |
| Cube | 8030037515625 |
| Square root | 141.509717 (= 15√89) |
| Digit sum / digital root | 9 / 9 |
| Collatz steps to 1 | 136 |
| Scientific notation | 2.0025 × |
20025 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand and twenty-five |
| Binary (base 2) | 100111000111001 |
| Octal (base 8) | 47071 |
| Hexadecimal (base 16) | 4E39 |
| Base 3 | 1000110200 |
| As time | 20025 seconds = 5 h 33 min 45 s |
Is 20025 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (20025 ÷ 3 = 6675) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (20025 ÷ 5 = 4005) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (20025 ÷ 9 = 2225) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 5) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20025 a prime number?
No. 20025 = × × 89, so it is divisible by 3.
What are the factors of 20025?
1, 3, 5, 9, 15, 25, 45, 75, 89, 225, 267, 445, 801, 1335, 2225, 4005, 6675, 20025.
What is 20025 in binary?
100111000111001 (hexadecimal 4E39, octal 47071).
What is the square root of 20025?
About 141.5097, exactly 15√89.
Is 20025 divisible by 3?
Yes. Its digits add up to 9, a multiple of 3.
What is special about the number 20025?
20025 is a binary palindrome (100111000111001); a Harshad number: divisible by its digit sum 9.