The number 72749
72749 is a composite number with 4 divisors. Its prime factorisation is 23 × 3163. Divisors (4): 1, 23, 3163, 72749.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 72749: a semiprime: 23 × 3163, the product of two primes.
- 2
72749 is composite. Its prime factorisation is
- 3
The divisors add up to 75936; without 72749 itself that is 3187, so 72749 is deficient (3187 is less than 72749). Euler's totient φ(72749) = 69564 numbers up to 72749 share no factor with it.
- 4
The digits of 72749 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 68 steps to reach 1.
LaTeX source of the formulas on this page
\[ 72749 = 23 \times 3163 \]
72749 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 75936 |
| Euler totient φ(n) | 69564 |
| Square | 5292417001 |
| Cube | 385018044405749 |
| Square root | 269.720225 |
| Digit sum / digital root | 29 / 2 |
| Collatz steps to 1 | 68 |
| Scientific notation | 7.2749 × |
72749 in other forms
| Form | Value |
|---|---|
| In words | seventy-two thousand seven hundred and forty-nine |
| Binary (base 2) | 10001110000101101 |
| Octal (base 8) | 216055 |
| Hexadecimal (base 16) | 11C2D |
| Base 3 | 10200210102 |
| As time | 72749 seconds = 20 h 12 min 29 s |
Is 72749 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 | No (remainder 2) | 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 4) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 5) | 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 5) | 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 | No (remainder 9) | 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 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 72749 a prime number?
No. 72749 = 23 × 3163, so it is divisible by 23.
What are the factors of 72749?
1, 23, 3163, 72749.
What is 72749 in binary?
10001110000101101 (hexadecimal 11C2D, octal 216055).
What is the square root of 72749?
About 269.7202.
Is 72749 divisible by 3?
No. Its digits add up to 29, which is not a multiple of 3.
What is special about the number 72749?
72749 is a semiprime: 23 × 3163, the product of two primes.