The number 4321
4321 is a binary palindrome (1000011100001). Its prime factorisation is 29 × 149. Divisors (4): 1, 29, 149, 4321.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 4321: a binary palindrome (1000011100001); a semiprime: 29 × 149, the product of two primes.
- 2
4321 is composite. Its prime factorisation is
- 3
The divisors add up to 4500; without 4321 itself that is 179, so 4321 is deficient (179 is less than 4321). Euler's totient φ(4321) = 4144 numbers up to 4321 share no factor with it.
- 4
The digits of 4321 add up to 10, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 170 steps to reach 1.
LaTeX source of the formulas on this page
\[ 4321 = 29 \times 149 \]
4321 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 4500 |
| Euler totient φ(n) | 4144 |
| Square | 18671041 |
| Cube | 80677568161 |
| Square root | 65.734314 |
| Digit sum / digital root | 10 / 1 |
| Collatz steps to 1 | 170 |
| Scientific notation | 4.321 × |
4321 in other forms
| Form | Value |
|---|---|
| In words | four thousand three hundred and twenty-one |
| Binary (base 2) | 1000011100001 |
| Octal (base 8) | 10341 |
| Hexadecimal (base 16) | 10E1 |
| Base 3 | 12221001 |
| As time | 4321 seconds = 1 h 12 min 1 s |
Is 4321 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 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 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 2) | 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 1) | 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 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 4321 a prime number?
No. 4321 = 29 × 149, so it is divisible by 29.
What are the factors of 4321?
1, 29, 149, 4321.
What is 4321 in binary?
1000011100001 (hexadecimal 10E1, octal 10341).
What is the square root of 4321?
About 65.7343.
Is 4321 divisible by 3?
No. Its digits add up to 10, which is not a multiple of 3.
What is special about the number 4321?
4321 is a binary palindrome (1000011100001); a semiprime: 29 × 149, the product of two primes.