The number 31472
31472 is a composite number with 20 divisors. Its prime factorisation is × 7 × 281. Divisors (20): 1, 2, 4, 7, 8, 14, 16, 28, 56, 112, 281, 562, 1124, 1967, 2248, 3934 … 31472.
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How to work it out
- 1
What is special about 31472: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
31472 is composite. Its prime factorisation is
- 3
The divisors add up to 69936; without 31472 itself that is 38464, so 31472 is abundant (38464 is more than 31472). Euler's totient φ(31472) = 13440 numbers up to 31472 share no factor with it.
- 4
The digits of 31472 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 103 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31472 = 2^{4} \times 7 \times 281 \]31472 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 20 |
| Sum of divisors | 69936 |
| Euler totient φ(n) | 13440 |
| Square | 990486784 |
| Cube | 31172600066048 |
| Square root | 177.403495 (= 4√1967) |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 103 |
| Scientific notation | 3.1472 × |
31472 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand four hundred and seventy-two |
| Binary (base 2) | 111101011110000 |
| Octal (base 8) | 75360 |
| Hexadecimal (base 16) | 7AF0 |
| Base 3 | 1121011122 |
| As time | 31472 seconds = 8 h 44 min 32 s |
Is 31472 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31472 ÷ 2 = 15736) | 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 (31472 ÷ 4 = 7868) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 2) | 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 | Yes (31472 ÷ 7 = 4496) | 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 | Yes (31472 ÷ 8 = 3934) | 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 2) | 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 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31472 a prime number?
No. 31472 = × 7 × 281, so it is divisible by 2.
What are the factors of 31472?
1, 2, 4, 7, 8, 14, 16, 28, 56, 112, 281, 562, 1124, 1967, 2248, 3934, 4496, 7868, 15736, 31472.
What is 31472 in binary?
111101011110000 (hexadecimal 7AF0, octal 75360).
What is the square root of 31472?
About 177.4035, exactly 4√1967.
Is 31472 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 31472?
31472 is a happy number: repeatedly adding the squares of its digits reaches 1.