The number 31977
31977 is a composite number with 24 divisors. Its prime factorisation is × 11 × 17 × 19. Divisors (24): 1, 3, 9, 11, 17, 19, 33, 51, 57, 99, 153, 171, 187, 209, 323, 561 … 31977.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
31977 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
31977 is composite. Its prime factorisation is
- 3
The divisors add up to 56160; without 31977 itself that is 24183, so 31977 is deficient (24183 is less than 31977). Euler's totient φ(31977) = 17280 numbers up to 31977 share no factor with it.
- 4
The digits of 31977 add up to 27, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 191 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31977 = 3^{2} \times 11 \times 17 \times 19 \]31977 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 56160 |
| Euler totient φ(n) | 17280 |
| Square | 1022528529 |
| Cube | 32697394771833 |
| Square root | 178.821140 (= 3√3553) |
| Digit sum / digital root | 27 / 9 |
| Collatz steps to 1 | 191 |
| Scientific notation | 3.1977 × |
31977 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand nine hundred and seventy-seven |
| Binary (base 2) | 111110011101001 |
| Octal (base 8) | 76351 |
| Hexadecimal (base 16) | 7CE9 |
| Base 3 | 1121212100 |
| As time | 31977 seconds = 8 h 52 min 57 s |
Is 31977 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (31977 ÷ 3 = 10659) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 1) | 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 | No (remainder 3) | 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (31977 ÷ 9 = 3553) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 7) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (31977 ÷ 11 = 2907) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31977 a prime number?
No. 31977 = × 11 × 17 × 19, so it is divisible by 3.
What are the factors of 31977?
1, 3, 9, 11, 17, 19, 33, 51, 57, 99, 153, 171, 187, 209, 323, 561, 627, 969, 1683, 1881, 2907, 3553, 10659, 31977.
What is 31977 in binary?
111110011101001 (hexadecimal 7CE9, octal 76351).
What is the square root of 31977?
About 178.8211, exactly 3√3553.
Is 31977 divisible by 3?
Yes. Its digits add up to 27, a multiple of 3.
What is special about the number 31977?
It is a composite number with 24 divisors.