The number 396
396 is a composite number with 18 divisors. Its prime factorisation is × × 11. Divisors (18): 1, 2, 3, 4, 6, 9, 11, 12, 18, 22, 33, 36, 44, 66, 99, 132 … 396.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 396: a Harshad number: divisible by its digit sum 18.
- 2
396 is composite. Its prime factorisation is
- 3
The divisors add up to 1092; without 396 itself that is 696, so 396 is abundant (696 is more than 396). Euler's totient φ(396) = 120 numbers up to 396 share no factor with it.
- 4
The digits of 396 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 27 steps to reach 1.
LaTeX source of the formulas on this page
\[ 396 = 2^{2} \times 3^{2} \times 11 \]396 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 18 |
| Sum of divisors | 1092 |
| Euler totient φ(n) | 120 |
| Square | 156816 |
| Cube | 62099136 |
| Square root | 19.899749 (= 6√11) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 27 |
| Scientific notation | 3.96 × |
396 in other forms
| Form | Value |
|---|---|
| In words | three hundred and ninety-six |
| Roman numerals | CCCXCVI |
| Binary (base 2) | 110001100 |
| Octal (base 8) | 614 |
| Hexadecimal (base 16) | 18C |
| Base 3 | 112200 |
| As time | 396 seconds = 6 min 36 s |
Is 396 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (396 ÷ 2 = 198) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (396 ÷ 3 = 132) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (396 ÷ 4 = 99) | 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 | Yes (396 ÷ 6 = 66) | 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 4) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (396 ÷ 9 = 44) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 6) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (396 ÷ 11 = 36) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (396 ÷ 12 = 33) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 396 a prime number?
No. 396 = × × 11, so it is divisible by 2.
What are the factors of 396?
1, 2, 3, 4, 6, 9, 11, 12, 18, 22, 33, 36, 44, 66, 99, 132, 198, 396.
What is 396 in binary?
110001100 (hexadecimal 18C, octal 614).
What is the square root of 396?
About 19.8997, exactly 6√11.
What is 396 in Roman numerals?
CCCXCVI.
Is 396 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 396?
396 is a Harshad number: divisible by its digit sum 18.