The number 1212
1212 is a composite number with 12 divisors. Its prime factorisation is × 3 × 101. Divisors (12): 1, 2, 3, 4, 6, 12, 101, 202, 303, 404, 606, 1212.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1212: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 6.
- 2
1212 is composite. Its prime factorisation is
- 3
The divisors add up to 2856; without 1212 itself that is 1644, so 1212 is abundant (1644 is more than 1212). Euler's totient φ(1212) = 400 numbers up to 1212 share no factor with it.
- 4
The digits of 1212 add up to 6, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 44 steps to reach 1.
LaTeX source of the formulas on this page
\[ 1212 = 2^{2} \times 3 \times 101 \]1212 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 2856 |
| Euler totient φ(n) | 400 |
| Square | 1468944 |
| Cube | 1780360128 |
| Square root | 34.813790 (= 2√303) |
| Digit sum / digital root | 6 / 6 |
| Collatz steps to 1 | 44 |
| Scientific notation | 1.212 × |
1212 in other forms
| Form | Value |
|---|---|
| In words | one thousand two hundred and twelve |
| Roman numerals | MCCXII |
| Binary (base 2) | 10010111100 |
| Octal (base 8) | 2274 |
| Hexadecimal (base 16) | 4BC |
| Base 3 | 1122220 |
| As time | 1212 seconds = 20 min 12 s |
Is 1212 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (1212 ÷ 2 = 606) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (1212 ÷ 3 = 404) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (1212 ÷ 4 = 303) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 2) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (1212 ÷ 6 = 202) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 1) | 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 6) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 2) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (1212 ÷ 12 = 101) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 1212 a prime number?
No. 1212 = × 3 × 101, so it is divisible by 2.
What are the factors of 1212?
1, 2, 3, 4, 6, 12, 101, 202, 303, 404, 606, 1212.
What is 1212 in binary?
10010111100 (hexadecimal 4BC, octal 2274).
What is the square root of 1212?
About 34.8138, exactly 2√303.
What is 1212 in Roman numerals?
MCCXII.
Is 1212 divisible by 3?
Yes. Its digits add up to 6, a multiple of 3.
What is special about the number 1212?
1212 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 6.