The number 2138
2138 is a composite number with 4 divisors. Its prime factorisation is 2 × 1069. Divisors (4): 1, 2, 1069, 2138.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 2138: a semiprime: 2 × 1069, the product of two primes.
- 2
2138 is composite. Its prime factorisation is
- 3
The divisors add up to 3210; without 2138 itself that is 1072, so 2138 is deficient (1072 is less than 2138). Euler's totient φ(2138) = 1068 numbers up to 2138 share no factor with it.
- 4
The digits of 2138 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 24 steps to reach 1.
LaTeX source of the formulas on this page
\[ 2138 = 2 \times 1069 \]
2138 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 3210 |
| Euler totient φ(n) | 1068 |
| Square | 4571044 |
| Cube | 9772892072 |
| Square root | 46.238512 |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 24 |
| Scientific notation | 2.138 × |
2138 in other forms
| Form | Value |
|---|---|
| In words | two thousand one hundred and thirty-eight |
| Roman numerals | MMCXXXVIII |
| Binary (base 2) | 100001011010 |
| Octal (base 8) | 4132 |
| Hexadecimal (base 16) | 85A |
| Base 3 | 2221012 |
| As time | 2138 seconds = 35 min 38 s |
Is 2138 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (2138 ÷ 2 = 1069) | 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 | 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 2) | 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 2) | 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 | No (remainder 8) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 2138 a prime number?
No. 2138 = 2 × 1069, so it is divisible by 2.
What are the factors of 2138?
1, 2, 1069, 2138.
What is 2138 in binary?
100001011010 (hexadecimal 85A, octal 4132).
What is the square root of 2138?
About 46.2385.
What is 2138 in Roman numerals?
MMCXXXVIII.
Is 2138 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 2138?
2138 is a semiprime: 2 × 1069, the product of two primes.