The number 49721
49721 is a composite number with 4 divisors. Its prime factorisation is 7 × 7103. Divisors (4): 1, 7, 7103, 49721.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 49721: a semiprime: 7 × 7103, the product of two primes.
- 2
49721 is composite. Its prime factorisation is
- 3
The divisors add up to 56832; without 49721 itself that is 7111, so 49721 is deficient (7111 is less than 49721). Euler's totient φ(49721) = 42612 numbers up to 49721 share no factor with it.
- 4
The digits of 49721 add up to 23, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 189 steps to reach 1.
LaTeX source of the formulas on this page
\[ 49721 = 7 \times 7103 \]
49721 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 56832 |
| Euler totient φ(n) | 42612 |
| Square | 2472177841 |
| Cube | 122919154432361 |
| Square root | 222.982062 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 189 |
| Scientific notation | 4.9721 × |
49721 in other forms
| Form | Value |
|---|---|
| In words | forty-nine thousand seven hundred and twenty-one |
| Binary (base 2) | 1100001000111001 |
| Octal (base 8) | 141071 |
| Hexadecimal (base 16) | C239 |
| Base 3 | 2112012112 |
| As time | 49721 seconds = 13 h 48 min 41 s |
Is 49721 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 1) | 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 | Yes (49721 ÷ 7 = 7103) | 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 | No (remainder 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 1) | 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 49721 a prime number?
No. 49721 = 7 × 7103, so it is divisible by 7.
What are the factors of 49721?
1, 7, 7103, 49721.
What is 49721 in binary?
1100001000111001 (hexadecimal C239, octal 141071).
What is the square root of 49721?
About 222.9821.
Is 49721 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 49721?
49721 is a semiprime: 7 × 7103, the product of two primes.