The number 1825
1825 is a composite number with 6 divisors. Its prime factorisation is Ć 73. Divisors (6): 1, 5, 25, 73, 365, 1825.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1825: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
1825 is composite. Its prime factorisation is
- 3
The divisors add up to 2294; without 1825 itself that is 469, so 1825 is deficient (469 is less than 1825). Euler's totient Ļ(1825) = 1440 numbers up to 1825 share no factor with it.
- 4
The digits of 1825 add up to 16, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 42 steps to reach 1.
LaTeX source of the formulas on this page
\[ 1825 = 5^{2} \times 73 \]1825 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 2294 |
| Euler totient Ļ(n) | 1440 |
| Square | 3330625 |
| Cube | 6078390625 |
| Square root | 42.720019 (= 5ā73) |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 42 |
| Scientific notation | 1.825 Ć |
1825 in other forms
| Form | Value |
|---|---|
| In words | one thousand eight hundred and twenty-five |
| Roman numerals | MDCCCXXV |
| Binary (base 2) | 11100100001 |
| Octal (base 8) | 3441 |
| Hexadecimal (base 16) | 721 |
| Base 3 | 2111121 |
| As time | 1825 seconds = 30 min 25 s |
Is 1825 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 | No (remainder 1) | 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 (1825 Ć· 5 = 365) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 1) | 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 | No (remainder 7) | 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 10) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 1825 a prime number?
No. 1825 = Ć 73, so it is divisible by 5.
What are the factors of 1825?
1, 5, 25, 73, 365, 1825.
What is 1825 in binary?
11100100001 (hexadecimal 721, octal 3441).
What is the square root of 1825?
About 42.7200, exactly 5ā73.
What is 1825 in Roman numerals?
MDCCCXXV.
Is 1825 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 1825?
1825 is a happy number: repeatedly adding the squares of its digits reaches 1.