The number 13825
13825 is a composite number with 12 divisors. Its prime factorisation is × 7 × 79. Divisors (12): 1, 5, 7, 25, 35, 79, 175, 395, 553, 1975, 2765, 13825.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 13825: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
13825 is composite. Its prime factorisation is
- 3
The divisors add up to 19840; without 13825 itself that is 6015, so 13825 is deficient (6015 is less than 13825). Euler's totient φ(13825) = 9360 numbers up to 13825 share no factor with it.
- 4
The digits of 13825 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 89 steps to reach 1.
LaTeX source of the formulas on this page
\[ 13825 = 5^{2} \times 7 \times 79 \]13825 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 19840 |
| Euler totient φ(n) | 9360 |
| Square | 191130625 |
| Cube | 2642380890625 |
| Square root | 117.579760 (= 5√553) |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 89 |
| Scientific notation | 1.3825 × |
13825 in other forms
| Form | Value |
|---|---|
| In words | thirteen thousand eight hundred and twenty-five |
| Binary (base 2) | 11011000000001 |
| Octal (base 8) | 33001 |
| Hexadecimal (base 16) | 3601 |
| Base 3 | 200222001 |
| As time | 13825 seconds = 3 h 50 min 25 s |
Is 13825 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 (13825 ÷ 5 = 2765) | 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 | Yes (13825 ÷ 7 = 1975) | 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 1) | 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 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 13825 a prime number?
No. 13825 = × 7 × 79, so it is divisible by 5.
What are the factors of 13825?
1, 5, 7, 25, 35, 79, 175, 395, 553, 1975, 2765, 13825.
What is 13825 in binary?
11011000000001 (hexadecimal 3601, octal 33001).
What is the square root of 13825?
About 117.5798, exactly 5√553.
Is 13825 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 13825?
13825 is a happy number: repeatedly adding the squares of its digits reaches 1.