The number 40720
40720 is a composite number with 20 divisors. Its prime factorisation is × 5 × 509. Divisors (20): 1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 509, 1018, 2036, 2545, 4072, 5090 … 40720.
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How to work it out
- 1
40720 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
40720 is composite. Its prime factorisation is
- 3
The divisors add up to 94860; without 40720 itself that is 54140, so 40720 is abundant (54140 is more than 40720). Euler's totient φ(40720) = 16256 numbers up to 40720 share no factor with it.
- 4
The digits of 40720 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 44 steps to reach 1.
LaTeX source of the formulas on this page
\[ 40720 = 2^{4} \times 5 \times 509 \]40720 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 20 |
| Sum of divisors | 94860 |
| Euler totient φ(n) | 16256 |
| Square | 1658118400 |
| Cube | 67518581248000 |
| Square root | 201.791972 (= 4√2545) |
| Digit sum / digital root | 13 / 4 |
| Collatz steps to 1 | 44 |
| Scientific notation | 4.072 × |
40720 in other forms
| Form | Value |
|---|---|
| In words | forty thousand seven hundred and twenty |
| Binary (base 2) | 1001111100010000 |
| Octal (base 8) | 117420 |
| Hexadecimal (base 16) | 9F10 |
| Base 3 | 2001212011 |
| As time | 40720 seconds = 11 h 18 min 40 s |
Is 40720 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (40720 ÷ 2 = 20360) | 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 | Yes (40720 ÷ 4 = 10180) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (40720 ÷ 5 = 8144) | 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 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 | Yes (40720 ÷ 8 = 5090) | 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 (40720 ÷ 10 = 4072) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 40720 a prime number?
No. 40720 = × 5 × 509, so it is divisible by 2.
What are the factors of 40720?
1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 509, 1018, 2036, 2545, 4072, 5090, 8144, 10180, 20360, 40720.
What is 40720 in binary?
1001111100010000 (hexadecimal 9F10, octal 117420).
What is the square root of 40720?
About 201.7920, exactly 4√2545.
Is 40720 divisible by 3?
No. Its digits add up to 13, which is not a multiple of 3.
What is special about the number 40720?
It is a composite number with 20 divisors.