To find all the divisors of the number 40,140:
- 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 40,140:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
40,140 = 22 × 32 × 5 × 223
40,140 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 = (2 + 1) × (2 + 1) × (1 + 1) × (1 + 1) = 3 × 3 × 2 × 2 = 36
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 40,140
- 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 =
3
composite factor = 2
2 =
4
prime factor =
5
composite factor = 2 × 3 =
6
composite factor = 3
2 =
9
composite factor = 2 × 5 =
10
composite factor = 2
2 × 3 =
12
composite factor = 3 × 5 =
15
composite factor = 2 × 3
2 =
18
composite factor = 2
2 × 5 =
20
composite factor = 2 × 3 × 5 =
30
composite factor = 2
2 × 3
2 =
36
composite factor = 3
2 × 5 =
45
composite factor = 2
2 × 3 × 5 =
60
composite factor = 2 × 3
2 × 5 =
90
composite factor = 2
2 × 3
2 × 5 =
180
This list continues below...
... This list continues from above
prime factor =
223
composite factor = 2 × 223 =
446
composite factor = 3 × 223 =
669
composite factor = 2
2 × 223 =
892
composite factor = 5 × 223 =
1,115
composite factor = 2 × 3 × 223 =
1,338
composite factor = 3
2 × 223 =
2,007
composite factor = 2 × 5 × 223 =
2,230
composite factor = 2
2 × 3 × 223 =
2,676
composite factor = 3 × 5 × 223 =
3,345
composite factor = 2 × 3
2 × 223 =
4,014
composite factor = 2
2 × 5 × 223 =
4,460
composite factor = 2 × 3 × 5 × 223 =
6,690
composite factor = 2
2 × 3
2 × 223 =
8,028
composite factor = 3
2 × 5 × 223 =
10,035
composite factor = 2
2 × 3 × 5 × 223 =
13,380
composite factor = 2 × 3
2 × 5 × 223 =
20,070
composite factor = 2
2 × 3
2 × 5 × 223 =
40,140
36 factors (divisors)
What times what is 40,140?
What number multiplied by what number equals 40,140?
All the combinations of any two natural numbers whose product equals 40,140.
1 × 40,140 = 40,140
2 × 20,070 = 40,140
3 × 13,380 = 40,140
4 × 10,035 = 40,140
5 × 8,028 = 40,140
6 × 6,690 = 40,140
9 × 4,460 = 40,140
10 × 4,014 = 40,140
12 × 3,345 = 40,140
15 × 2,676 = 40,140
18 × 2,230 = 40,140
20 × 2,007 = 40,140
30 × 1,338 = 40,140
36 × 1,115 = 40,140
45 × 892 = 40,140
60 × 669 = 40,140
90 × 446 = 40,140
180 × 223 = 40,140
18 unique multiplications The final answer:
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