To find all the divisors of the number 78,000:
- 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 78,000:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
78,000 = 24 × 3 × 53 × 13
78,000 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 = (4 + 1) × (1 + 1) × (3 + 1) × (1 + 1) = 5 × 2 × 4 × 2 = 80
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 78,000
- 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 = 2
3 =
8
composite factor = 2 × 5 =
10
composite factor = 2
2 × 3 =
12
prime factor =
13
composite factor = 3 × 5 =
15
composite factor = 2
4 =
16
composite factor = 2
2 × 5 =
20
composite factor = 2
3 × 3 =
24
composite factor = 5
2 =
25
composite factor = 2 × 13 =
26
composite factor = 2 × 3 × 5 =
30
composite factor = 3 × 13 =
39
composite factor = 2
3 × 5 =
40
composite factor = 2
4 × 3 =
48
composite factor = 2 × 5
2 =
50
composite factor = 2
2 × 13 =
52
composite factor = 2
2 × 3 × 5 =
60
composite factor = 5 × 13 =
65
composite factor = 3 × 5
2 =
75
composite factor = 2 × 3 × 13 =
78
composite factor = 2
4 × 5 =
80
composite factor = 2
2 × 5
2 =
100
composite factor = 2
3 × 13 =
104
composite factor = 2
3 × 3 × 5 =
120
composite factor = 5
3 =
125
composite factor = 2 × 5 × 13 =
130
composite factor = 2 × 3 × 5
2 =
150
composite factor = 2
2 × 3 × 13 =
156
composite factor = 3 × 5 × 13 =
195
composite factor = 2
3 × 5
2 =
200
composite factor = 2
4 × 13 =
208
composite factor = 2
4 × 3 × 5 =
240
composite factor = 2 × 5
3 =
250
composite factor = 2
2 × 5 × 13 =
260
This list continues below...
... This list continues from above
composite factor = 2
2 × 3 × 5
2 =
300
composite factor = 2
3 × 3 × 13 =
312
composite factor = 5
2 × 13 =
325
composite factor = 3 × 5
3 =
375
composite factor = 2 × 3 × 5 × 13 =
390
composite factor = 2
4 × 5
2 =
400
composite factor = 2
2 × 5
3 =
500
composite factor = 2
3 × 5 × 13 =
520
composite factor = 2
3 × 3 × 5
2 =
600
composite factor = 2
4 × 3 × 13 =
624
composite factor = 2 × 5
2 × 13 =
650
composite factor = 2 × 3 × 5
3 =
750
composite factor = 2
2 × 3 × 5 × 13 =
780
composite factor = 3 × 5
2 × 13 =
975
composite factor = 2
3 × 5
3 =
1,000
composite factor = 2
4 × 5 × 13 =
1,040
composite factor = 2
4 × 3 × 5
2 =
1,200
composite factor = 2
2 × 5
2 × 13 =
1,300
composite factor = 2
2 × 3 × 5
3 =
1,500
composite factor = 2
3 × 3 × 5 × 13 =
1,560
composite factor = 5
3 × 13 =
1,625
composite factor = 2 × 3 × 5
2 × 13 =
1,950
composite factor = 2
4 × 5
3 =
2,000
composite factor = 2
3 × 5
2 × 13 =
2,600
composite factor = 2
3 × 3 × 5
3 =
3,000
composite factor = 2
4 × 3 × 5 × 13 =
3,120
composite factor = 2 × 5
3 × 13 =
3,250
composite factor = 2
2 × 3 × 5
2 × 13 =
3,900
composite factor = 3 × 5
3 × 13 =
4,875
composite factor = 2
4 × 5
2 × 13 =
5,200
composite factor = 2
4 × 3 × 5
3 =
6,000
composite factor = 2
2 × 5
3 × 13 =
6,500
composite factor = 2
3 × 3 × 5
2 × 13 =
7,800
composite factor = 2 × 3 × 5
3 × 13 =
9,750
composite factor = 2
3 × 5
3 × 13 =
13,000
composite factor = 2
4 × 3 × 5
2 × 13 =
15,600
composite factor = 2
2 × 3 × 5
3 × 13 =
19,500
composite factor = 2
4 × 5
3 × 13 =
26,000
composite factor = 2
3 × 3 × 5
3 × 13 =
39,000
composite factor = 2
4 × 3 × 5
3 × 13 =
78,000
80 factors (divisors)
What times what is 78,000?
What number multiplied by what number equals 78,000?
All the combinations of any two natural numbers whose product equals 78,000.
1 × 78,000 = 78,000
2 × 39,000 = 78,000
3 × 26,000 = 78,000
4 × 19,500 = 78,000
5 × 15,600 = 78,000
6 × 13,000 = 78,000
8 × 9,750 = 78,000
10 × 7,800 = 78,000
12 × 6,500 = 78,000
13 × 6,000 = 78,000
15 × 5,200 = 78,000
16 × 4,875 = 78,000
20 × 3,900 = 78,000
24 × 3,250 = 78,000
25 × 3,120 = 78,000
26 × 3,000 = 78,000
30 × 2,600 = 78,000
39 × 2,000 = 78,000
40 × 1,950 = 78,000
48 × 1,625 = 78,000
50 × 1,560 = 78,000
52 × 1,500 = 78,000
60 × 1,300 = 78,000
65 × 1,200 = 78,000
75 × 1,040 = 78,000
78 × 1,000 = 78,000
80 × 975 = 78,000
100 × 780 = 78,000
104 × 750 = 78,000
120 × 650 = 78,000
125 × 624 = 78,000
130 × 600 = 78,000
150 × 520 = 78,000
156 × 500 = 78,000
195 × 400 = 78,000
200 × 390 = 78,000
208 × 375 = 78,000
240 × 325 = 78,000
250 × 312 = 78,000
260 × 300 = 78,000
40 unique multiplications The final answer:
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