The number 31003
31003 is a composite number with 8 divisors. Its prime factorisation is 7 × 43 × 103. Divisors (8): 1, 7, 43, 103, 301, 721, 4429, 31003.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31003: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 7.
- 2
31003 is composite. Its prime factorisation is
- 3
The divisors add up to 36608; without 31003 itself that is 5605, so 31003 is deficient (5605 is less than 31003). Euler's totient φ(31003) = 25704 numbers up to 31003 share no factor with it.
- 4
The digits of 31003 add up to 7, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 160 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31003 = 7 \times 43 \times 103 \]
31003 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 36608 |
| Euler totient φ(n) | 25704 |
| Square | 961186009 |
| Cube | 29799649837027 |
| Square root | 176.076688 |
| Digit sum / digital root | 7 / 7 |
| Collatz steps to 1 | 160 |
| Scientific notation | 3.1003 × |
31003 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand and three |
| Binary (base 2) | 111100100011011 |
| Octal (base 8) | 74433 |
| Hexadecimal (base 16) | 791B |
| Base 3 | 1120112021 |
| As time | 31003 seconds = 8 h 36 min 43 s |
Is 31003 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 | Yes (31003 ÷ 7 = 4429) | 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 7) | 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 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31003 a prime number?
No. 31003 = 7 × 43 × 103, so it is divisible by 7.
What are the factors of 31003?
1, 7, 43, 103, 301, 721, 4429, 31003.
What is 31003 in binary?
111100100011011 (hexadecimal 791B, octal 74433).
What is the square root of 31003?
About 176.0767.
Is 31003 divisible by 3?
No. Its digits add up to 7, which is not a multiple of 3.
What is special about the number 31003?
31003 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 7.