To find all the divisors of the number 138,320:
- 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 138,320:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
138,320 = 24 × 5 × 7 × 13 × 19
138,320 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) × (1 + 1) × (1 + 1) × (1 + 1) = 5 × 2 × 2 × 2 × 2 = 80
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 138,320
- 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
composite factor = 2
2 =
4
prime factor =
5
prime factor =
7
composite factor = 2
3 =
8
composite factor = 2 × 5 =
10
prime factor =
13
composite factor = 2 × 7 =
14
composite factor = 2
4 =
16
prime factor =
19
composite factor = 2
2 × 5 =
20
composite factor = 2 × 13 =
26
composite factor = 2
2 × 7 =
28
composite factor = 5 × 7 =
35
composite factor = 2 × 19 =
38
composite factor = 2
3 × 5 =
40
composite factor = 2
2 × 13 =
52
composite factor = 2
3 × 7 =
56
composite factor = 5 × 13 =
65
composite factor = 2 × 5 × 7 =
70
composite factor = 2
2 × 19 =
76
composite factor = 2
4 × 5 =
80
composite factor = 7 × 13 =
91
composite factor = 5 × 19 =
95
composite factor = 2
3 × 13 =
104
composite factor = 2
4 × 7 =
112
composite factor = 2 × 5 × 13 =
130
composite factor = 7 × 19 =
133
composite factor = 2
2 × 5 × 7 =
140
composite factor = 2
3 × 19 =
152
composite factor = 2 × 7 × 13 =
182
composite factor = 2 × 5 × 19 =
190
composite factor = 2
4 × 13 =
208
composite factor = 13 × 19 =
247
composite factor = 2
2 × 5 × 13 =
260
composite factor = 2 × 7 × 19 =
266
composite factor = 2
3 × 5 × 7 =
280
composite factor = 2
4 × 19 =
304
composite factor = 2
2 × 7 × 13 =
364
This list continues below...
... This list continues from above
composite factor = 2
2 × 5 × 19 =
380
composite factor = 5 × 7 × 13 =
455
composite factor = 2 × 13 × 19 =
494
composite factor = 2
3 × 5 × 13 =
520
composite factor = 2
2 × 7 × 19 =
532
composite factor = 2
4 × 5 × 7 =
560
composite factor = 5 × 7 × 19 =
665
composite factor = 2
3 × 7 × 13 =
728
composite factor = 2
3 × 5 × 19 =
760
composite factor = 2 × 5 × 7 × 13 =
910
composite factor = 2
2 × 13 × 19 =
988
composite factor = 2
4 × 5 × 13 =
1,040
composite factor = 2
3 × 7 × 19 =
1,064
composite factor = 5 × 13 × 19 =
1,235
composite factor = 2 × 5 × 7 × 19 =
1,330
composite factor = 2
4 × 7 × 13 =
1,456
composite factor = 2
4 × 5 × 19 =
1,520
composite factor = 7 × 13 × 19 =
1,729
composite factor = 2
2 × 5 × 7 × 13 =
1,820
composite factor = 2
3 × 13 × 19 =
1,976
composite factor = 2
4 × 7 × 19 =
2,128
composite factor = 2 × 5 × 13 × 19 =
2,470
composite factor = 2
2 × 5 × 7 × 19 =
2,660
composite factor = 2 × 7 × 13 × 19 =
3,458
composite factor = 2
3 × 5 × 7 × 13 =
3,640
composite factor = 2
4 × 13 × 19 =
3,952
composite factor = 2
2 × 5 × 13 × 19 =
4,940
composite factor = 2
3 × 5 × 7 × 19 =
5,320
composite factor = 2
2 × 7 × 13 × 19 =
6,916
composite factor = 2
4 × 5 × 7 × 13 =
7,280
composite factor = 5 × 7 × 13 × 19 =
8,645
composite factor = 2
3 × 5 × 13 × 19 =
9,880
composite factor = 2
4 × 5 × 7 × 19 =
10,640
composite factor = 2
3 × 7 × 13 × 19 =
13,832
composite factor = 2 × 5 × 7 × 13 × 19 =
17,290
composite factor = 2
4 × 5 × 13 × 19 =
19,760
composite factor = 2
4 × 7 × 13 × 19 =
27,664
composite factor = 2
2 × 5 × 7 × 13 × 19 =
34,580
composite factor = 2
3 × 5 × 7 × 13 × 19 =
69,160
composite factor = 2
4 × 5 × 7 × 13 × 19 =
138,320
80 factors (divisors)
What times what is 138,320?
What number multiplied by what number equals 138,320?
All the combinations of any two natural numbers whose product equals 138,320.
1 × 138,320 = 138,320
2 × 69,160 = 138,320
4 × 34,580 = 138,320
5 × 27,664 = 138,320
7 × 19,760 = 138,320
8 × 17,290 = 138,320
10 × 13,832 = 138,320
13 × 10,640 = 138,320
14 × 9,880 = 138,320
16 × 8,645 = 138,320
19 × 7,280 = 138,320
20 × 6,916 = 138,320
26 × 5,320 = 138,320
28 × 4,940 = 138,320
35 × 3,952 = 138,320
38 × 3,640 = 138,320
40 × 3,458 = 138,320
52 × 2,660 = 138,320
56 × 2,470 = 138,320
65 × 2,128 = 138,320
70 × 1,976 = 138,320
76 × 1,820 = 138,320
80 × 1,729 = 138,320
91 × 1,520 = 138,320
95 × 1,456 = 138,320
104 × 1,330 = 138,320
112 × 1,235 = 138,320
130 × 1,064 = 138,320
133 × 1,040 = 138,320
140 × 988 = 138,320
152 × 910 = 138,320
182 × 760 = 138,320
190 × 728 = 138,320
208 × 665 = 138,320
247 × 560 = 138,320
260 × 532 = 138,320
266 × 520 = 138,320
280 × 494 = 138,320
304 × 455 = 138,320
364 × 380 = 138,320
40 unique multiplications The final answer:
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