The number 102
102 is a composite number with 8 divisors. Its prime factorisation is 2 × 3 × 17. Divisors (8): 1, 2, 3, 6, 17, 34, 51, 102.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 102: a Harshad number: divisible by its digit sum 3.
- 2
102 is composite. Its prime factorisation is
- 3
The divisors add up to 216; without 102 itself that is 114, so 102 is abundant (114 is more than 102). Euler's totient φ(102) = 32 numbers up to 102 share no factor with it.
- 4
The digits of 102 add up to 3, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 25 steps to reach 1.
LaTeX source of the formulas on this page
\[ 102 = 2 \times 3 \times 17 \]
102 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 216 |
| Euler totient φ(n) | 32 |
| Square | 10404 |
| Cube | 1061208 |
| Square root | 10.099505 |
| Digit sum / digital root | 3 / 3 |
| Collatz steps to 1 | 25 |
| Scientific notation | 1.02 × |
102 in other forms
| Form | Value |
|---|---|
| In words | one hundred and two |
| Roman numerals | CII |
| Binary (base 2) | 1100110 |
| Octal (base 8) | 146 |
| Hexadecimal (base 16) | 66 |
| Base 3 | 10210 |
| As time | 102 seconds = 1 min 42 s |
Is 102 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (102 ÷ 2 = 51) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (102 ÷ 3 = 34) | 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 2) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (102 ÷ 6 = 17) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 4) | 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 3) | 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 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 6) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 102 a prime number?
No. 102 = 2 × 3 × 17, so it is divisible by 2.
What are the factors of 102?
1, 2, 3, 6, 17, 34, 51, 102.
What is 102 in binary?
1100110 (hexadecimal 66, octal 146).
What is the square root of 102?
About 10.0995.
What is 102 in Roman numerals?
CII.
Is 102 divisible by 3?
Yes. Its digits add up to 3, a multiple of 3.
What is special about the number 102?
102 is a Harshad number: divisible by its digit sum 3.