The number 20003
20003 is a composite number with 4 divisors. Its prime factorisation is 83 × 241. Divisors (4): 1, 83, 241, 20003.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 20003: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 83 × 241, the product of two primes.
- 2
20003 is composite. Its prime factorisation is
- 3
The divisors add up to 20328; without 20003 itself that is 325, so 20003 is deficient (325 is less than 20003). Euler's totient φ(20003) = 19680 numbers up to 20003 share no factor with it.
- 4
The digits of 20003 add up to 5, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 180 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20003 = 83 \times 241 \]
20003 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 20328 |
| Euler totient φ(n) | 19680 |
| Square | 400120009 |
| Cube | 8003600540027 |
| Square root | 141.431962 |
| Digit sum / digital root | 5 / 5 |
| Collatz steps to 1 | 180 |
| Scientific notation | 2.0003 × |
20003 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand and three |
| Binary (base 2) | 100111000100011 |
| Octal (base 8) | 47043 |
| Hexadecimal (base 16) | 4E23 |
| Base 3 | 1000102212 |
| As time | 20003 seconds = 5 h 33 min 23 s |
Is 20003 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 4) | 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 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 5) | 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 20003 a prime number?
No. 20003 = 83 × 241, so it is divisible by 83.
What are the factors of 20003?
1, 83, 241, 20003.
What is 20003 in binary?
100111000100011 (hexadecimal 4E23, octal 47043).
What is the square root of 20003?
About 141.4320.
Is 20003 divisible by 3?
No. Its digits add up to 5, which is not a multiple of 3.
What is special about the number 20003?
20003 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 83 × 241, the product of two primes.