The number 725
725 is a composite number with 6 divisors. Its prime factorisation is Ć 29. Divisors (6): 1, 5, 25, 29, 145, 725.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
725 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
725 is composite. Its prime factorisation is
- 3
The divisors add up to 930; without 725 itself that is 205, so 725 is deficient (205 is less than 725). Euler's totient Ļ(725) = 560 numbers up to 725 share no factor with it.
- 4
The digits of 725 add up to 14, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 20 steps to reach 1.
LaTeX source of the formulas on this page
\[ 725 = 5^{2} \times 29 \]725 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 930 |
| Euler totient Ļ(n) | 560 |
| Square | 525625 |
| Cube | 381078125 |
| Square root | 26.925824 (= 5ā29) |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 20 |
| Scientific notation | 7.25 Ć |
725 in other forms
| Form | Value |
|---|---|
| In words | seven hundred and twenty-five |
| Roman numerals | DCCXXV |
| Binary (base 2) | 1011010101 |
| Octal (base 8) | 1325 |
| Hexadecimal (base 16) | 2D5 |
| Base 3 | 222212 |
| As time | 725 seconds = 12 min 5 s |
Is 725 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 2) | 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 (725 Ć· 5 = 145) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 4) | 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 5) | 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 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 725 a prime number?
No. 725 = Ć 29, so it is divisible by 5.
What are the factors of 725?
1, 5, 25, 29, 145, 725.
What is 725 in binary?
1011010101 (hexadecimal 2D5, octal 1325).
What is the square root of 725?
About 26.9258, exactly 5ā29.
What is 725 in Roman numerals?
DCCXXV.
Is 725 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 725?
It is a composite number with 6 divisors.