The number 31090
31090 is a composite number with 8 divisors. Its prime factorisation is 2 × 5 × 3109. Divisors (8): 1, 2, 5, 10, 3109, 6218, 15545, 31090.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31090: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
31090 is composite. Its prime factorisation is
- 3
The divisors add up to 55980; without 31090 itself that is 24890, so 31090 is deficient (24890 is less than 31090). Euler's totient φ(31090) = 12432 numbers up to 31090 share no factor with it.
- 4
The digits of 31090 add up to 13, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 116 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31090 = 2 \times 5 \times 3109 \]
31090 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 55980 |
| Euler totient φ(n) | 12432 |
| Square | 966588100 |
| Cube | 30051224029000 |
| Square root | 176.323566 |
| Digit sum / digital root | 13 / 4 |
| Collatz steps to 1 | 116 |
| Scientific notation | 3.109 × |
31090 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand and ninety |
| Binary (base 2) | 111100101110010 |
| Octal (base 8) | 74562 |
| Hexadecimal (base 16) | 7972 |
| Base 3 | 1120122111 |
| As time | 31090 seconds = 8 h 38 min 10 s |
Is 31090 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31090 ÷ 2 = 15545) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | 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 | Yes (31090 ÷ 5 = 6218) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | 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 | No (remainder 4) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (31090 ÷ 10 = 3109) | 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 | No (remainder 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31090 a prime number?
No. 31090 = 2 × 5 × 3109, so it is divisible by 2.
What are the factors of 31090?
1, 2, 5, 10, 3109, 6218, 15545, 31090.
What is 31090 in binary?
111100101110010 (hexadecimal 7972, octal 74562).
What is the square root of 31090?
About 176.3236.
Is 31090 divisible by 3?
No. Its digits add up to 13, which is not a multiple of 3.
What is special about the number 31090?
31090 is a happy number: repeatedly adding the squares of its digits reaches 1.