The number 77423
77423 is a composite number with 4 divisors. Its prime factorisation is 139 × 557. Divisors (4): 1, 139, 557, 77423.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 77423: a semiprime: 139 × 557, the product of two primes.
- 2
77423 is composite. Its prime factorisation is
- 3
The divisors add up to 78120; without 77423 itself that is 697, so 77423 is deficient (697 is less than 77423). Euler's totient φ(77423) = 76728 numbers up to 77423 share no factor with it.
- 4
The digits of 77423 add up to 23, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 156 steps to reach 1.
LaTeX source of the formulas on this page
\[ 77423 = 139 \times 557 \]
77423 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 78120 |
| Euler totient φ(n) | 76728 |
| Square | 5994320929 |
| Cube | 464098309285967 |
| Square root | 278.249888 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 156 |
| Scientific notation | 7.7423 × |
77423 in other forms
| Form | Value |
|---|---|
| In words | seventy-seven thousand four hundred and twenty-three |
| Binary (base 2) | 10010111001101111 |
| Octal (base 8) | 227157 |
| Hexadecimal (base 16) | 12E6F |
| Base 3 | 10221012112 |
| As time | 77423 seconds = 21 h 30 min 23 s |
Is 77423 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 2) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | 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 5) | 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 7) | 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 3) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 77423 a prime number?
No. 77423 = 139 × 557, so it is divisible by 139.
What are the factors of 77423?
1, 139, 557, 77423.
What is 77423 in binary?
10010111001101111 (hexadecimal 12E6F, octal 227157).
What is the square root of 77423?
About 278.2499.
Is 77423 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 77423?
77423 is a semiprime: 139 × 557, the product of two primes.