The number 72740
72740 is a composite number with 12 divisors. Its prime factorisation is × 5 × 3637. Divisors (12): 1, 2, 4, 5, 10, 20, 3637, 7274, 14548, 18185, 36370, 72740.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 72740: a Harshad number: divisible by its digit sum 20.
- 2
72740 is composite. Its prime factorisation is
- 3
The divisors add up to 152796; without 72740 itself that is 80056, so 72740 is abundant (80056 is more than 72740). Euler's totient φ(72740) = 29088 numbers up to 72740 share no factor with it.
- 4
The digits of 72740 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 81 steps to reach 1.
LaTeX source of the formulas on this page
\[ 72740 = 2^{2} \times 5 \times 3637 \]72740 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 152796 |
| Euler totient φ(n) | 29088 |
| Square | 5291107600 |
| Cube | 384875166824000 |
| Square root | 269.703541 (= 2√18185) |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 81 |
| Scientific notation | 7.274 × |
72740 in other forms
| Form | Value |
|---|---|
| In words | seventy-two thousand seven hundred and forty |
| Binary (base 2) | 10001110000100100 |
| Octal (base 8) | 216044 |
| Hexadecimal (base 16) | 11C24 |
| Base 3 | 10200210002 |
| As time | 72740 seconds = 20 h 12 min 20 s |
Is 72740 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (72740 ÷ 2 = 36370) | 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 (72740 ÷ 4 = 18185) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (72740 ÷ 5 = 14548) | 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 (72740 ÷ 10 = 7274) | 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 72740 a prime number?
No. 72740 = × 5 × 3637, so it is divisible by 2.
What are the factors of 72740?
1, 2, 4, 5, 10, 20, 3637, 7274, 14548, 18185, 36370, 72740.
What is 72740 in binary?
10001110000100100 (hexadecimal 11C24, octal 216044).
What is the square root of 72740?
About 269.7035, exactly 2√18185.
Is 72740 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 72740?
72740 is a Harshad number: divisible by its digit sum 20.