The number 72671
72671 is a twin prime (72671 and 72673 are both prime) and the 7186th prime number. Its only divisors are 1 and 72671.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 72671: a twin prime (72671 and 72673 are both prime); the 7186th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
72671 is prime, so its only factors are 1 and 72671. It is the 7186th prime; the next prime is 72673 and the one before is 72661.
- 3
The divisors add up to 72672; without 72671 itself that is 1, so 72671 is deficient (1 is less than 72671). Euler's totient φ(72671) = 72670 numbers up to 72671 share no factor with it.
- 4
The digits of 72671 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 99 steps to reach 1.
72671 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 72672 |
| Euler totient φ(n) | 72670 |
| Square | 5281074241 |
| Cube | 383780946167711 |
| Square root | 269.575592 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 99 |
| Scientific notation | 7.2671 × |
72671 in other forms
| Form | Value |
|---|---|
| In words | seventy-two thousand six hundred and seventy-one |
| Binary (base 2) | 10001101111011111 |
| Octal (base 8) | 215737 |
| Hexadecimal (base 16) | 11BDF |
| Base 3 | 10200200112 |
| As time | 72671 seconds = 20 h 11 min 11 s |
Is 72671 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 3) | 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 | No (remainder 4) | 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 7) | 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 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 72671 a prime number?
Yes. 72671 is divisible only by 1 and itself.
What are the factors of 72671?
1, 72671.
What is 72671 in binary?
10001101111011111 (hexadecimal 11BDF, octal 215737).
What is the square root of 72671?
About 269.5756.
Is 72671 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 72671?
72671 is a twin prime (72671 and 72673 are both prime); the 7186th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.