The number 31122
31122 is a composite number with 48 divisors. Its prime factorisation is 2 × × 7 × 13 × 19. Divisors (48): 1, 2, 3, 6, 7, 9, 13, 14, 18, 19, 21, 26, 38, 39, 42, 57 … 31122.
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How to work it out
- 1
What is special about 31122: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 9.
- 2
31122 is composite. Its prime factorisation is
- 3
The divisors add up to 87360; without 31122 itself that is 56238, so 31122 is abundant (56238 is more than 31122). Euler's totient φ(31122) = 7776 numbers up to 31122 share no factor with it.
- 4
The digits of 31122 add up to 9, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 85 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31122 = 2 \times 3^{2} \times 7 \times 13 \times 19 \]31122 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 48 |
| Sum of divisors | 87360 |
| Euler totient φ(n) | 7776 |
| Square | 968578884 |
| Cube | 30144112027848 |
| Square root | 176.414285 (= 3√3458) |
| Digit sum / digital root | 9 / 9 |
| Collatz steps to 1 | 85 |
| Scientific notation | 3.1122 × |
31122 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand one hundred and twenty-two |
| Binary (base 2) | 111100110010010 |
| Octal (base 8) | 74622 |
| Hexadecimal (base 16) | 7992 |
| Base 3 | 1120200200 |
| As time | 31122 seconds = 8 h 38 min 42 s |
Is 31122 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31122 ÷ 2 = 15561) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (31122 ÷ 3 = 10374) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 2) | 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 (31122 ÷ 6 = 5187) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (31122 ÷ 7 = 4446) | 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (31122 ÷ 9 = 3458) | 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 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 6) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31122 a prime number?
No. 31122 = 2 × × 7 × 13 × 19, so it is divisible by 2.
What are the factors of 31122?
1, 2, 3, 6, 7, 9, 13, 14, 18, 19, 21, 26, 38, 39, 42, 57, 63, 78, 91, 114, 117, 126, 133, 171, 182, 234, 247, 266, 273, 342, 399, 494, 546, 741, 798, 819, 1197, 1482, 1638, 1729, 2223, 2394, 3458, 4446, 5187, 10374, 15561, 31122.
What is 31122 in binary?
111100110010010 (hexadecimal 7992, octal 74622).
What is the square root of 31122?
About 176.4143, exactly 3√3458.
Is 31122 divisible by 3?
Yes. Its digits add up to 9, a multiple of 3.
What is special about the number 31122?
31122 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 9.