The number 73421
73421 is the 7251st prime number. Its only divisors are 1 and 73421.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 73421: the 7251st prime number; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
73421 is prime, so its only factors are 1 and 73421. It is the 7251st prime; the next prime is 73433 and the one before is 73417.
- 3
The divisors add up to 73422; without 73421 itself that is 1, so 73421 is deficient (1 is less than 73421). Euler's totient φ(73421) = 73420 numbers up to 73421 share no factor with it.
- 4
The digits of 73421 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 112 steps to reach 1.
73421 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 73422 |
| Euler totient φ(n) | 73420 |
| Square | 5390643241 |
| Cube | 395786417397461 |
| Square root | 270.963097 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 112 |
| Scientific notation | 7.3421 × |
73421 in other forms
| Form | Value |
|---|---|
| In words | seventy-three thousand four hundred and twenty-one |
| Binary (base 2) | 10001111011001101 |
| Octal (base 8) | 217315 |
| Hexadecimal (base 16) | 11ECD |
| Base 3 | 10201201022 |
| As time | 73421 seconds = 20 h 23 min 41 s |
Is 73421 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 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 8) | 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 7) | 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 73421 a prime number?
Yes. 73421 is divisible only by 1 and itself.
What are the factors of 73421?
1, 73421.
What is 73421 in binary?
10001111011001101 (hexadecimal 11ECD, octal 217315).
What is the square root of 73421?
About 270.9631.
Is 73421 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 73421?
73421 is the 7251st prime number; a happy number: repeatedly adding the squares of its digits reaches 1.