The number 1393
1393 is a composite number with 4 divisors. Its prime factorisation is 7 × 199. Divisors (4): 1, 7, 199, 1393.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1393: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 7 × 199, the product of two primes.
- 2
1393 is composite. Its prime factorisation is
- 3
The divisors add up to 1600; without 1393 itself that is 207, so 1393 is deficient (207 is less than 1393). Euler's totient φ(1393) = 1188 numbers up to 1393 share no factor with it.
- 4
The digits of 1393 add up to 16, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 34 steps to reach 1.
LaTeX source of the formulas on this page
\[ 1393 = 7 \times 199 \]
1393 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 1600 |
| Euler totient φ(n) | 1188 |
| Square | 1940449 |
| Cube | 2703045457 |
| Square root | 37.322915 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 34 |
| Scientific notation | 1.393 × |
1393 in other forms
| Form | Value |
|---|---|
| In words | one thousand three hundred and ninety-three |
| Roman numerals | MCCCXCIII |
| Binary (base 2) | 10101110001 |
| Octal (base 8) | 2561 |
| Hexadecimal (base 16) | 571 |
| Base 3 | 1220121 |
| As time | 1393 seconds = 23 min 13 s |
Is 1393 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | 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 | No (remainder 1) | 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 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (1393 ÷ 7 = 199) | 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 3) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 1393 a prime number?
No. 1393 = 7 × 199, so it is divisible by 7.
What are the factors of 1393?
1, 7, 199, 1393.
What is 1393 in binary?
10101110001 (hexadecimal 571, octal 2561).
What is the square root of 1393?
About 37.3229.
What is 1393 in Roman numerals?
MCCCXCIII.
Is 1393 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 1393?
1393 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 7 × 199, the product of two primes.