To find all the divisors of the number 642,158:
- 1. Decompose the number into prime factors.
- See how you can find out how many factors (divisors) the number has, without actually calculating them.
- 2. Multiply the prime factors in all their unique combinations, that yield different results.
1. Carry out the prime factorization of the number 642,158:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
642,158 = 2 × 11 × 172 × 101
642,158 is not a prime number but a composite one.
- Prime number: a natural number that is divisible (divided evenly) only by 1 and itself. A prime number has exactly two factors: 1 and the number itself.
- Examples of prime numbers: 2 (factors 1, 2), 3 (factors 1, 3), 5 (factors 1, 5), 7 (factors 1, 7), 11 (factors 1, 11), 13 (factors 1, 13), ...
- Composite number: a natural number that has at least one factor other than 1 and itself. So it is neither a prime number nor 1.
- Examples of composite numbers: 4 (it has 3 factors: 1, 2, 4), 6 (it has 4 factors: 1, 2, 3, 6), 8 (it has 4 factors: 1, 2, 4, 8), 9 (it has 3 factors: 1, 3, 9), 10 (it has 4 factors: 1, 2, 5, 10), 12 (it has 6 factors: 1, 2, 3, 4, 6, 12), ...
How to count the number of factors of a number?
Without actually finding the factors
- If a number N is prime factorized as:
N = am × bk × cz
where a, b, c are the prime factors and m, k, z are their exponents, natural numbers, .... - ...
- Then the number of factors of the number N can be calculated as:
n = (m + 1) × (k + 1) × (z + 1) - ...
- In our case, the number of factors is calculated as:
- n = (1 + 1) × (1 + 1) × (2 + 1) × (1 + 1) = 2 × 2 × 3 × 2 = 24
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 642,158
- Multiply the prime factors involved in the prime factorization of the number in all their unique combinations, that give different results.
- Also consider the exponents of these prime factors.
- Also add 1 to the list of factors (divisors). All the numbers are divisible by 1.
All the factors (divisors) are listed below - in ascending order
The list of factors (divisors):
Numbers other than 1 that are not prime factors are composite factors (divisors).
neither prime nor composite =
1
prime factor =
2
prime factor =
11
prime factor =
17
composite factor = 2 × 11 =
22
composite factor = 2 × 17 =
34
prime factor =
101
composite factor = 11 × 17 =
187
composite factor = 2 × 101 =
202
composite factor = 17
2 =
289
composite factor = 2 × 11 × 17 =
374
composite factor = 2 × 17
2 =
578
This list continues below...
... This list continues from above
composite factor = 11 × 101 =
1,111
composite factor = 17 × 101 =
1,717
composite factor = 2 × 11 × 101 =
2,222
composite factor = 11 × 17
2 =
3,179
composite factor = 2 × 17 × 101 =
3,434
composite factor = 2 × 11 × 17
2 =
6,358
composite factor = 11 × 17 × 101 =
18,887
composite factor = 17
2 × 101 =
29,189
composite factor = 2 × 11 × 17 × 101 =
37,774
composite factor = 2 × 17
2 × 101 =
58,378
composite factor = 11 × 17
2 × 101 =
321,079
composite factor = 2 × 11 × 17
2 × 101 =
642,158
24 factors (divisors)
What times what is 642,158?
What number multiplied by what number equals 642,158?
All the combinations of any two natural numbers whose product equals 642,158.
1 × 642,158 = 642,158
2 × 321,079 = 642,158
11 × 58,378 = 642,158
17 × 37,774 = 642,158
22 × 29,189 = 642,158
34 × 18,887 = 642,158
101 × 6,358 = 642,158
187 × 3,434 = 642,158
202 × 3,179 = 642,158
289 × 2,222 = 642,158
374 × 1,717 = 642,158
578 × 1,111 = 642,158
12 unique multiplications The final answer:
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