The number 72143
72143 is a composite number with 4 divisors. Its prime factorisation is 19 × 3797. Divisors (4): 1, 19, 3797, 72143.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 72143: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 19 × 3797, the product of two primes.
- 2
72143 is composite. Its prime factorisation is
- 3
The divisors add up to 75960; without 72143 itself that is 3817, so 72143 is deficient (3817 is less than 72143). Euler's totient φ(72143) = 68328 numbers up to 72143 share no factor with it.
- 4
The digits of 72143 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 94 steps to reach 1.
LaTeX source of the formulas on this page
\[ 72143 = 19 \times 3797 \]
72143 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 75960 |
| Euler totient φ(n) | 68328 |
| Square | 5204612449 |
| Cube | 375476355908207 |
| Square root | 268.594490 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 94 |
| Scientific notation | 7.2143 × |
72143 in other forms
| Form | Value |
|---|---|
| In words | seventy-two thousand one hundred and forty-three |
| Binary (base 2) | 10001100111001111 |
| Octal (base 8) | 214717 |
| Hexadecimal (base 16) | 119CF |
| Base 3 | 10122221222 |
| As time | 72143 seconds = 20 h 2 min 23 s |
Is 72143 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 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | 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 1) | 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 8) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 3) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 72143 a prime number?
No. 72143 = 19 × 3797, so it is divisible by 19.
What are the factors of 72143?
1, 19, 3797, 72143.
What is 72143 in binary?
10001100111001111 (hexadecimal 119CF, octal 214717).
What is the square root of 72143?
About 268.5945.
Is 72143 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 72143?
72143 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 19 × 3797, the product of two primes.