The number 143
143 is a composite number with 4 divisors. Its prime factorisation is 11 × 13. Divisors (4): 1, 11, 13, 143.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 143: a semiprime: 11 × 13, the product of two primes.
- 2
143 is composite. Its prime factorisation is
- 3
The divisors add up to 168; without 143 itself that is 25, so 143 is deficient (25 is less than 143). Euler's totient φ(143) = 120 numbers up to 143 share no factor with it.
- 4
The digits of 143 add up to 8, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 103 steps to reach 1.
LaTeX source of the formulas on this page
\[ 143 = 11 \times 13 \]
143 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 168 |
| Euler totient φ(n) | 120 |
| Square | 20449 |
| Cube | 2924207 |
| Square root | 11.958261 |
| Digit sum / digital root | 8 / 8 |
| Collatz steps to 1 | 103 |
| Scientific notation | 1.43 × |
143 in other forms
| Form | Value |
|---|---|
| In words | one hundred and forty-three |
| Roman numerals | CXLIII |
| Binary (base 2) | 10001111 |
| Octal (base 8) | 217 |
| Hexadecimal (base 16) | 8F |
| Base 3 | 12022 |
| As time | 143 seconds = 2 min 23 s |
Is 143 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 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 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 | Yes (143 ÷ 11 = 13) | 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 143 a prime number?
No. 143 = 11 × 13, so it is divisible by 11.
What are the factors of 143?
1, 11, 13, 143.
What is 143 in binary?
10001111 (hexadecimal 8F, octal 217).
What is the square root of 143?
About 11.9583.
What is 143 in Roman numerals?
CXLIII.
Is 143 divisible by 3?
No. Its digits add up to 8, which is not a multiple of 3.
What is special about the number 143?
143 is a semiprime: 11 × 13, the product of two primes.