The number 39980
39980 is a composite number with 12 divisors. Its prime factorisation is × 5 × 1999. Divisors (12): 1, 2, 4, 5, 10, 20, 1999, 3998, 7996, 9995, 19990, 39980.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
39980 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
39980 is composite. Its prime factorisation is
- 3
The divisors add up to 84000; without 39980 itself that is 44020, so 39980 is abundant (44020 is more than 39980). Euler's totient φ(39980) = 15984 numbers up to 39980 share no factor with it.
- 4
The digits of 39980 add up to 29, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 67 steps to reach 1.
LaTeX source of the formulas on this page
\[ 39980 = 2^{2} \times 5 \times 1999 \]39980 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 84000 |
| Euler totient φ(n) | 15984 |
| Square | 1598400400 |
| Cube | 63904047992000 |
| Square root | 199.949994 (= 2√9995) |
| Digit sum / digital root | 29 / 2 |
| Collatz steps to 1 | 67 |
| Scientific notation | 3.998 × |
39980 in other forms
| Form | Value |
|---|---|
| In words | thirty-nine thousand nine hundred and eighty |
| Binary (base 2) | 1001110000101100 |
| Octal (base 8) | 116054 |
| Hexadecimal (base 16) | 9C2C |
| Base 3 | 2000211202 |
| As time | 39980 seconds = 11 h 6 min 20 s |
Is 39980 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (39980 ÷ 2 = 19990) | 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 (39980 ÷ 4 = 9995) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (39980 ÷ 5 = 7996) | 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 | 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 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 | Yes (39980 ÷ 10 = 3998) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 6) | 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 39980 a prime number?
No. 39980 = × 5 × 1999, so it is divisible by 2.
What are the factors of 39980?
1, 2, 4, 5, 10, 20, 1999, 3998, 7996, 9995, 19990, 39980.
What is 39980 in binary?
1001110000101100 (hexadecimal 9C2C, octal 116054).
What is the square root of 39980?
About 199.9500, exactly 2√9995.
Is 39980 divisible by 3?
No. Its digits add up to 29, which is not a multiple of 3.
What is special about the number 39980?
It is a composite number with 12 divisors.