The number 1236
1236 is a composite number with 12 divisors. Its prime factorisation is × 3 × 103. Divisors (12): 1, 2, 3, 4, 6, 12, 103, 206, 309, 412, 618, 1236.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1236: a Harshad number: divisible by its digit sum 12.
- 2
1236 is composite. Its prime factorisation is
- 3
The divisors add up to 2912; without 1236 itself that is 1676, so 1236 is abundant (1676 is more than 1236). Euler's totient φ(1236) = 408 numbers up to 1236 share no factor with it.
- 4
The digits of 1236 add up to 12, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 26 steps to reach 1.
LaTeX source of the formulas on this page
\[ 1236 = 2^{2} \times 3 \times 103 \]1236 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 2912 |
| Euler totient φ(n) | 408 |
| Square | 1527696 |
| Cube | 1888232256 |
| Square root | 35.156792 (= 2√309) |
| Digit sum / digital root | 12 / 3 |
| Collatz steps to 1 | 26 |
| Scientific notation | 1.236 × |
1236 in other forms
| Form | Value |
|---|---|
| In words | one thousand two hundred and thirty-six |
| Roman numerals | MCCXXXVI |
| Binary (base 2) | 10011010100 |
| Octal (base 8) | 2324 |
| Hexadecimal (base 16) | 4D4 |
| Base 3 | 1200210 |
| As time | 1236 seconds = 20 min 36 s |
Is 1236 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (1236 ÷ 2 = 618) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (1236 ÷ 3 = 412) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (1236 ÷ 4 = 309) | 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 (1236 ÷ 6 = 206) | 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 | No (remainder 3) | 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 | No (remainder 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (1236 ÷ 12 = 103) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 1236 a prime number?
No. 1236 = × 3 × 103, so it is divisible by 2.
What are the factors of 1236?
1, 2, 3, 4, 6, 12, 103, 206, 309, 412, 618, 1236.
What is 1236 in binary?
10011010100 (hexadecimal 4D4, octal 2324).
What is the square root of 1236?
About 35.1568, exactly 2√309.
What is 1236 in Roman numerals?
MCCXXXVI.
Is 1236 divisible by 3?
Yes. Its digits add up to 12, a multiple of 3.
What is special about the number 1236?
1236 is a Harshad number: divisible by its digit sum 12.