The number 1725
1725 is a composite number with 12 divisors. Its prime factorisation is 3 × × 23. Divisors (12): 1, 3, 5, 15, 23, 25, 69, 75, 115, 345, 575, 1725.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1725: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 15.
- 2
1725 is composite. Its prime factorisation is
- 3
The divisors add up to 2976; without 1725 itself that is 1251, so 1725 is deficient (1251 is less than 1725). Euler's totient φ(1725) = 880 numbers up to 1725 share no factor with it.
- 4
The digits of 1725 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 42 steps to reach 1.
LaTeX source of the formulas on this page
\[ 1725 = 3 \times 5^{2} \times 23 \]1725 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 2976 |
| Euler totient φ(n) | 880 |
| Square | 2975625 |
| Cube | 5132953125 |
| Square root | 41.533119 (= 5√69) |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 42 |
| Scientific notation | 1.725 × |
1725 in other forms
| Form | Value |
|---|---|
| In words | one thousand seven hundred and twenty-five |
| Roman numerals | MDCCXXV |
| Binary (base 2) | 11010111101 |
| Octal (base 8) | 3275 |
| Hexadecimal (base 16) | 6BD |
| Base 3 | 2100220 |
| As time | 1725 seconds = 28 min 45 s |
Is 1725 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 (1725 ÷ 3 = 575) | 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 (1725 ÷ 5 = 345) | 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 3) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | 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 9) | 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 1725 a prime number?
No. 1725 = 3 × × 23, so it is divisible by 3.
What are the factors of 1725?
1, 3, 5, 15, 23, 25, 69, 75, 115, 345, 575, 1725.
What is 1725 in binary?
11010111101 (hexadecimal 6BD, octal 3275).
What is the square root of 1725?
About 41.5331, exactly 5√69.
What is 1725 in Roman numerals?
MDCCXXV.
Is 1725 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 1725?
1725 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 15.