The number 1543
1543 is the 243rd prime number. Its only divisors are 1 and 1543.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1543: the 243rd prime number.
- 2
1543 is prime, so its only factors are 1 and 1543. It is the 243rd prime; the next prime is 1549 and the one before is 1531.
- 3
The divisors add up to 1544; without 1543 itself that is 1, so 1543 is deficient (1 is less than 1543). Euler's totient φ(1543) = 1542 numbers up to 1543 share no factor with it.
- 4
The digits of 1543 add up to 13, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 109 steps to reach 1.
1543 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 1544 |
| Euler totient φ(n) | 1542 |
| Square | 2380849 |
| Cube | 3673650007 |
| Square root | 39.281039 |
| Digit sum / digital root | 13 / 4 |
| Collatz steps to 1 | 109 |
| Scientific notation | 1.543 × |
1543 in other forms
| Form | Value |
|---|---|
| In words | one thousand five hundred and forty-three |
| Roman numerals | MDXLIII |
| Binary (base 2) | 11000000111 |
| Octal (base 8) | 3007 |
| Hexadecimal (base 16) | 607 |
| Base 3 | 2010011 |
| As time | 1543 seconds = 25 min 43 s |
Is 1543 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 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 1) | 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 4) | 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 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 1543 a prime number?
Yes. 1543 is divisible only by 1 and itself.
What are the factors of 1543?
1, 1543.
What is 1543 in binary?
11000000111 (hexadecimal 607, octal 3007).
What is the square root of 1543?
About 39.2810.
What is 1543 in Roman numerals?
MDXLIII.
Is 1543 divisible by 3?
No. Its digits add up to 13, which is not a multiple of 3.
What is special about the number 1543?
1543 is the 243rd prime number.