The number 72478
72478 is a composite number with 16 divisors. Its prime factorisation is 2 × 7 × 31 × 167. Divisors (16): 1, 2, 7, 14, 31, 62, 167, 217, 334, 434, 1169, 2338, 5177, 10354, 36239, 72478.
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How to work it out
- 1
72478 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
72478 is composite. Its prime factorisation is
- 3
The divisors add up to 129024; without 72478 itself that is 56546, so 72478 is deficient (56546 is less than 72478). Euler's totient φ(72478) = 29880 numbers up to 72478 share no factor with it.
- 4
The digits of 72478 add up to 28, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 42 steps to reach 1.
LaTeX source of the formulas on this page
\[ 72478 = 2 \times 7 \times 31 \times 167 \]
72478 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 129024 |
| Euler totient φ(n) | 29880 |
| Square | 5253060484 |
| Cube | 380731317759352 |
| Square root | 269.217384 |
| Digit sum / digital root | 28 / 1 |
| Collatz steps to 1 | 42 |
| Scientific notation | 7.2478 × |
72478 in other forms
| Form | Value |
|---|---|
| In words | seventy-two thousand four hundred and seventy-eight |
| Binary (base 2) | 10001101100011110 |
| Octal (base 8) | 215436 |
| Hexadecimal (base 16) | 11B1E |
| Base 3 | 10200102101 |
| As time | 72478 seconds = 20 h 7 min 58 s |
Is 72478 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (72478 ÷ 2 = 36239) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 2) | 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 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (72478 ÷ 7 = 10354) | 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 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 8) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 10) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 72478 a prime number?
No. 72478 = 2 × 7 × 31 × 167, so it is divisible by 2.
What are the factors of 72478?
1, 2, 7, 14, 31, 62, 167, 217, 334, 434, 1169, 2338, 5177, 10354, 36239, 72478.
What is 72478 in binary?
10001101100011110 (hexadecimal 11B1E, octal 215436).
What is the square root of 72478?
About 269.2174.
Is 72478 divisible by 3?
No. Its digits add up to 28, which is not a multiple of 3.
What is special about the number 72478?
It is a composite number with 16 divisors.