The number 73121
73121 is the 7229th prime number. Its only divisors are 1 and 73121.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 73121: the 7229th prime number.
- 2
73121 is prime, so its only factors are 1 and 73121. It is the 7229th prime; the next prime is 73127 and the one before is 73091.
- 3
The divisors add up to 73122; without 73121 itself that is 1, so 73121 is deficient (1 is less than 73121). Euler's totient φ(73121) = 73120 numbers up to 73121 share no factor with it.
- 4
The digits of 73121 add up to 14, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 68 steps to reach 1.
73121 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 73122 |
| Euler totient φ(n) | 73120 |
| Square | 5346680641 |
| Cube | 390954635150561 |
| Square root | 270.408950 |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 68 |
| Scientific notation | 7.3121 × |
73121 in other forms
| Form | Value |
|---|---|
| In words | seventy-three thousand one hundred and twenty-one |
| Binary (base 2) | 10001110110100001 |
| Octal (base 8) | 216641 |
| Hexadecimal (base 16) | 11DA1 |
| Base 3 | 10201022012 |
| As time | 73121 seconds = 20 h 18 min 41 s |
Is 73121 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 | No (remainder 6) | 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 4) | 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 73121 a prime number?
Yes. 73121 is divisible only by 1 and itself.
What are the factors of 73121?
1, 73121.
What is 73121 in binary?
10001110110100001 (hexadecimal 11DA1, octal 216641).
What is the square root of 73121?
About 270.4089.
Is 73121 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 73121?
73121 is the 7229th prime number.