The number 2628
2628 is a triangular number: 1 + 2 + … + 72 = 2628. Its prime factorisation is × × 73. Divisors (18): 1, 2, 3, 4, 6, 9, 12, 18, 36, 73, 146, 219, 292, 438, 657, 876 … 2628.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 2628: a triangular number: 1 + 2 + … + 72 = 2628; a Harshad number: divisible by its digit sum 18.
- 2
2628 is composite. Its prime factorisation is
- 3
The divisors add up to 6734; without 2628 itself that is 4106, so 2628 is abundant (4106 is more than 2628). Euler's totient φ(2628) = 864 numbers up to 2628 share no factor with it.
- 4
The digits of 2628 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 53 steps to reach 1.
LaTeX source of the formulas on this page
\[ 2628 = 2^{2} \times 3^{2} \times 73 \]2628 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 18 |
| Sum of divisors | 6734 |
| Euler totient φ(n) | 864 |
| Square | 6906384 |
| Cube | 18149977152 |
| Square root | 51.264022 (= 6√73) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 53 |
| Scientific notation | 2.628 × |
2628 in other forms
| Form | Value |
|---|---|
| In words | two thousand six hundred and twenty-eight |
| Roman numerals | MMDCXXVIII |
| Binary (base 2) | 101001000100 |
| Octal (base 8) | 5104 |
| Hexadecimal (base 16) | A44 |
| Base 3 | 10121100 |
| As time | 2628 seconds = 43 min 48 s |
Is 2628 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (2628 ÷ 2 = 1314) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (2628 ÷ 3 = 876) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (2628 ÷ 4 = 657) | 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 | Yes (2628 ÷ 6 = 438) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | 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 | Yes (2628 ÷ 9 = 292) | 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 | Yes (2628 ÷ 12 = 219) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 2628 a prime number?
No. 2628 = × × 73, so it is divisible by 2.
What are the factors of 2628?
1, 2, 3, 4, 6, 9, 12, 18, 36, 73, 146, 219, 292, 438, 657, 876, 1314, 2628.
What is 2628 in binary?
101001000100 (hexadecimal A44, octal 5104).
What is the square root of 2628?
About 51.2640, exactly 6√73.
What is 2628 in Roman numerals?
MMDCXXVIII.
Is 2628 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 2628?
2628 is a triangular number: 1 + 2 + … + 72 = 2628; a Harshad number: divisible by its digit sum 18.