The number 71025
71025 is a composite number with 12 divisors. Its prime factorisation is 3 × × 947. Divisors (12): 1, 3, 5, 15, 25, 75, 947, 2841, 4735, 14205, 23675, 71025.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 71025: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 15.
- 2
71025 is composite. Its prime factorisation is
- 3
The divisors add up to 117552; without 71025 itself that is 46527, so 71025 is deficient (46527 is less than 71025). Euler's totient φ(71025) = 37840 numbers up to 71025 share no factor with it.
- 4
The digits of 71025 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 99 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71025 = 3 \times 5^{2} \times 947 \]71025 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 117552 |
| Euler totient φ(n) | 37840 |
| Square | 5044550625 |
| Cube | 358289208140625 |
| Square root | 266.505159 (= 5√2841) |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 99 |
| Scientific notation | 7.1025 × |
71025 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand and twenty-five |
| Binary (base 2) | 10001010101110001 |
| Octal (base 8) | 212561 |
| Hexadecimal (base 16) | 11571 |
| Base 3 | 10121102120 |
| As time | 71025 seconds = 19 h 43 min 45 s |
Is 71025 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 (71025 ÷ 3 = 23675) | 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 (71025 ÷ 5 = 14205) | 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 1) | 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 71025 a prime number?
No. 71025 = 3 × × 947, so it is divisible by 3.
What are the factors of 71025?
1, 3, 5, 15, 25, 75, 947, 2841, 4735, 14205, 23675, 71025.
What is 71025 in binary?
10001010101110001 (hexadecimal 11571, octal 212561).
What is the square root of 71025?
About 266.5052, exactly 5√2841.
Is 71025 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 71025?
71025 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 15.