The number 71001
71001 is a composite number with 24 divisors. Its prime factorisation is × × 23. Divisors (24): 1, 3, 7, 9, 21, 23, 49, 63, 69, 147, 161, 207, 343, 441, 483, 1029 … 71001.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 71001: a Harshad number: divisible by its digit sum 9.
- 2
71001 is composite. Its prime factorisation is
- 3
The divisors add up to 124800; without 71001 itself that is 53799, so 71001 is deficient (53799 is less than 71001). Euler's totient φ(71001) = 38808 numbers up to 71001 share no factor with it.
- 4
The digits of 71001 add up to 9, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 218 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71001 = 3^{2} \times 7^{3} \times 23 \]71001 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 124800 |
| Euler totient φ(n) | 38808 |
| Square | 5041142001 |
| Cube | 357926123213001 |
| Square root | 266.460128 (= 21√161) |
| Digit sum / digital root | 9 / 9 |
| Collatz steps to 1 | 218 |
| Scientific notation | 7.1001 × |
71001 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand and one |
| Binary (base 2) | 10001010101011001 |
| Octal (base 8) | 212531 |
| Hexadecimal (base 16) | 11559 |
| Base 3 | 10121101200 |
| As time | 71001 seconds = 19 h 43 min 21 s |
Is 71001 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 (71001 ÷ 3 = 23667) | 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 | No (remainder 1) | 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 | Yes (71001 ÷ 7 = 10143) | 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 | Yes (71001 ÷ 9 = 7889) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 7) | 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 71001 a prime number?
No. 71001 = × × 23, so it is divisible by 3.
What are the factors of 71001?
1, 3, 7, 9, 21, 23, 49, 63, 69, 147, 161, 207, 343, 441, 483, 1029, 1127, 1449, 3087, 3381, 7889, 10143, 23667, 71001.
What is 71001 in binary?
10001010101011001 (hexadecimal 11559, octal 212531).
What is the square root of 71001?
About 266.4601, exactly 21√161.
Is 71001 divisible by 3?
Yes. Its digits add up to 9, a multiple of 3.
What is special about the number 71001?
71001 is a Harshad number: divisible by its digit sum 9.