The number 71420
71420 is a composite number with 12 divisors. Its prime factorisation is × 5 × 3571. Divisors (12): 1, 2, 4, 5, 10, 20, 3571, 7142, 14284, 17855, 35710, 71420.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 71420: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
71420 is composite. Its prime factorisation is
- 3
The divisors add up to 150024; without 71420 itself that is 78604, so 71420 is abundant (78604 is more than 71420). Euler's totient φ(71420) = 28560 numbers up to 71420 share no factor with it.
- 4
The digits of 71420 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 125 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71420 = 2^{2} \times 5 \times 3571 \]71420 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 150024 |
| Euler totient φ(n) | 28560 |
| Square | 5100816400 |
| Cube | 364300307288000 |
| Square root | 267.245206 (= 2√17855) |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 125 |
| Scientific notation | 7.142 × |
71420 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand four hundred and twenty |
| Binary (base 2) | 10001011011111100 |
| Octal (base 8) | 213374 |
| Hexadecimal (base 16) | 116FC |
| Base 3 | 10121222012 |
| As time | 71420 seconds = 19 h 50 min 20 s |
Is 71420 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (71420 ÷ 2 = 35710) | 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 | Yes (71420 ÷ 4 = 17855) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (71420 ÷ 5 = 14284) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 2) | 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 4) | 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 | Yes (71420 ÷ 10 = 7142) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 71420 a prime number?
No. 71420 = × 5 × 3571, so it is divisible by 2.
What are the factors of 71420?
1, 2, 4, 5, 10, 20, 3571, 7142, 14284, 17855, 35710, 71420.
What is 71420 in binary?
10001011011111100 (hexadecimal 116FC, octal 213374).
What is the square root of 71420?
About 267.2452, exactly 2√17855.
Is 71420 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 71420?
71420 is a happy number: repeatedly adding the squares of its digits reaches 1.