The number 3100
3100 is a composite number with 18 divisors. Its prime factorisation is × × 31. Divisors (18): 1, 2, 4, 5, 10, 20, 25, 31, 50, 62, 100, 124, 155, 310, 620, 775 … 3100.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 3100: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 4.
- 2
3100 is composite. Its prime factorisation is
- 3
The divisors add up to 6944; without 3100 itself that is 3844, so 3100 is abundant (3844 is more than 3100). Euler's totient φ(3100) = 1200 numbers up to 3100 share no factor with it.
- 4
The digits of 3100 add up to 4, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 154 steps to reach 1.
LaTeX source of the formulas on this page
\[ 3100 = 2^{2} \times 5^{2} \times 31 \]3100 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 18 |
| Sum of divisors | 6944 |
| Euler totient φ(n) | 1200 |
| Square | 9610000 |
| Cube | 29791000000 |
| Square root | 55.677644 (= 10√31) |
| Digit sum / digital root | 4 / 4 |
| Collatz steps to 1 | 154 |
| Scientific notation | 3.1 × |
3100 in other forms
| Form | Value |
|---|---|
| In words | three thousand one hundred |
| Roman numerals | MMMC |
| Binary (base 2) | 110000011100 |
| Octal (base 8) | 6034 |
| Hexadecimal (base 16) | C1C |
| Base 3 | 11020211 |
| As time | 3100 seconds = 51 min 40 s |
Is 3100 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (3100 ÷ 2 = 1550) | 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 | Yes (3100 ÷ 4 = 775) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (3100 ÷ 5 = 620) | 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 | 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 4) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (3100 ÷ 10 = 310) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 3100 a prime number?
No. 3100 = × × 31, so it is divisible by 2.
What are the factors of 3100?
1, 2, 4, 5, 10, 20, 25, 31, 50, 62, 100, 124, 155, 310, 620, 775, 1550, 3100.
What is 3100 in binary?
110000011100 (hexadecimal C1C, octal 6034).
What is the square root of 3100?
About 55.6776, exactly 10√31.
What is 3100 in Roman numerals?
MMMC.
Is 3100 divisible by 3?
No. Its digits add up to 4, which is not a multiple of 3.
What is special about the number 3100?
3100 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 4.