The number 31556
31556 is a composite number with 24 divisors. Its prime factorisation is × × 23. Divisors (24): 1, 2, 4, 7, 14, 23, 28, 46, 49, 92, 98, 161, 196, 322, 343, 644 … 31556.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
31556 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
31556 is composite. Its prime factorisation is
- 3
The divisors add up to 67200; without 31556 itself that is 35644, so 31556 is abundant (35644 is more than 31556). Euler's totient φ(31556) = 12936 numbers up to 31556 share no factor with it.
- 4
The digits of 31556 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 103 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31556 = 2^{2} \times 7^{3} \times 23 \]31556 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 67200 |
| Euler totient φ(n) | 12936 |
| Square | 995781136 |
| Cube | 31422869527616 |
| Square root | 177.640086 (= 14√161) |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 103 |
| Scientific notation | 3.1556 × |
31556 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand five hundred and fifty-six |
| Binary (base 2) | 111101101000100 |
| Octal (base 8) | 75504 |
| Hexadecimal (base 16) | 7B44 |
| Base 3 | 1121021202 |
| As time | 31556 seconds = 8 h 45 min 56 s |
Is 31556 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31556 ÷ 2 = 15778) | 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 | Yes (31556 ÷ 4 = 7889) | 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 | No (remainder 2) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (31556 ÷ 7 = 4508) | 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 2) | 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 8) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31556 a prime number?
No. 31556 = × × 23, so it is divisible by 2.
What are the factors of 31556?
1, 2, 4, 7, 14, 23, 28, 46, 49, 92, 98, 161, 196, 322, 343, 644, 686, 1127, 1372, 2254, 4508, 7889, 15778, 31556.
What is 31556 in binary?
111101101000100 (hexadecimal 7B44, octal 75504).
What is the square root of 31556?
About 177.6401, exactly 14√161.
Is 31556 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 31556?
It is a composite number with 24 divisors.