The number 47213
47213 is a composite number with 4 divisors. Its prime factorisation is 31 × 1523. Divisors (4): 1, 31, 1523, 47213.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 47213: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 31 × 1523, the product of two primes.
- 2
47213 is composite. Its prime factorisation is
- 3
The divisors add up to 48768; without 47213 itself that is 1555, so 47213 is deficient (1555 is less than 47213). Euler's totient φ(47213) = 45660 numbers up to 47213 share no factor with it.
- 4
The digits of 47213 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 83 steps to reach 1.
LaTeX source of the formulas on this page
\[ 47213 = 31 \times 1523 \]
47213 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 48768 |
| Euler totient φ(n) | 45660 |
| Square | 2229067369 |
| Cube | 105240957692597 |
| Square root | 217.285526 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 83 |
| Scientific notation | 4.7213 × |
47213 in other forms
| Form | Value |
|---|---|
| In words | forty-seven thousand two hundred and thirteen |
| Binary (base 2) | 1011100001101101 |
| Octal (base 8) | 134155 |
| Hexadecimal (base 16) | B86D |
| Base 3 | 2101202122 |
| As time | 47213 seconds = 13 h 6 min 53 s |
Is 47213 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 3) | 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 3) | 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 47213 a prime number?
No. 47213 = 31 × 1523, so it is divisible by 31.
What are the factors of 47213?
1, 31, 1523, 47213.
What is 47213 in binary?
1011100001101101 (hexadecimal B86D, octal 134155).
What is the square root of 47213?
About 217.2855.
Is 47213 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 47213?
47213 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 31 × 1523, the product of two primes.