The number 803
803 is a composite number with 4 divisors. Its prime factorisation is 11 × 73. Divisors (4): 1, 11, 73, 803.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 803: a Harshad number: divisible by its digit sum 11; a semiprime: 11 × 73, the product of two primes.
- 2
803 is composite. Its prime factorisation is
- 3
The divisors add up to 888; without 803 itself that is 85, so 803 is deficient (85 is less than 803). Euler's totient φ(803) = 720 numbers up to 803 share no factor with it.
- 4
The digits of 803 add up to 11, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 20 steps to reach 1.
LaTeX source of the formulas on this page
\[ 803 = 11 \times 73 \]
803 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 888 |
| Euler totient φ(n) | 720 |
| Square | 644809 |
| Cube | 517781627 |
| Square root | 28.337255 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 20 |
| Scientific notation | 8.03 × |
803 in other forms
| Form | Value |
|---|---|
| In words | eight hundred and three |
| Roman numerals | DCCCIII |
| Binary (base 2) | 1100100011 |
| Octal (base 8) | 1443 |
| Hexadecimal (base 16) | 323 |
| Base 3 | 1002202 |
| As time | 803 seconds = 13 min 23 s |
Is 803 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 5) | 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 2) | 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 (803 ÷ 11 = 73) | 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 803 a prime number?
No. 803 = 11 × 73, so it is divisible by 11.
What are the factors of 803?
1, 11, 73, 803.
What is 803 in binary?
1100100011 (hexadecimal 323, octal 1443).
What is the square root of 803?
About 28.3373.
What is 803 in Roman numerals?
DCCCIII.
Is 803 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 803?
803 is a Harshad number: divisible by its digit sum 11; a semiprime: 11 × 73, the product of two primes.