To find all the divisors of the number 77,880:
- 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 77,880:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
77,880 = 23 × 3 × 5 × 11 × 59
77,880 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 = (3 + 1) × (1 + 1) × (1 + 1) × (1 + 1) × (1 + 1) = 4 × 2 × 2 × 2 × 2 = 64
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 77,880
- 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
prime factor =
11
composite factor = 2
2 × 3 =
12
composite factor = 3 × 5 =
15
composite factor = 2
2 × 5 =
20
composite factor = 2 × 11 =
22
composite factor = 2
3 × 3 =
24
composite factor = 2 × 3 × 5 =
30
composite factor = 3 × 11 =
33
composite factor = 2
3 × 5 =
40
composite factor = 2
2 × 11 =
44
composite factor = 5 × 11 =
55
prime factor =
59
composite factor = 2
2 × 3 × 5 =
60
composite factor = 2 × 3 × 11 =
66
composite factor = 2
3 × 11 =
88
composite factor = 2 × 5 × 11 =
110
composite factor = 2 × 59 =
118
composite factor = 2
3 × 3 × 5 =
120
composite factor = 2
2 × 3 × 11 =
132
composite factor = 3 × 5 × 11 =
165
composite factor = 3 × 59 =
177
composite factor = 2
2 × 5 × 11 =
220
composite factor = 2
2 × 59 =
236
composite factor = 2
3 × 3 × 11 =
264
This list continues below...
... This list continues from above
composite factor = 5 × 59 =
295
composite factor = 2 × 3 × 5 × 11 =
330
composite factor = 2 × 3 × 59 =
354
composite factor = 2
3 × 5 × 11 =
440
composite factor = 2
3 × 59 =
472
composite factor = 2 × 5 × 59 =
590
composite factor = 11 × 59 =
649
composite factor = 2
2 × 3 × 5 × 11 =
660
composite factor = 2
2 × 3 × 59 =
708
composite factor = 3 × 5 × 59 =
885
composite factor = 2
2 × 5 × 59 =
1,180
composite factor = 2 × 11 × 59 =
1,298
composite factor = 2
3 × 3 × 5 × 11 =
1,320
composite factor = 2
3 × 3 × 59 =
1,416
composite factor = 2 × 3 × 5 × 59 =
1,770
composite factor = 3 × 11 × 59 =
1,947
composite factor = 2
3 × 5 × 59 =
2,360
composite factor = 2
2 × 11 × 59 =
2,596
composite factor = 5 × 11 × 59 =
3,245
composite factor = 2
2 × 3 × 5 × 59 =
3,540
composite factor = 2 × 3 × 11 × 59 =
3,894
composite factor = 2
3 × 11 × 59 =
5,192
composite factor = 2 × 5 × 11 × 59 =
6,490
composite factor = 2
3 × 3 × 5 × 59 =
7,080
composite factor = 2
2 × 3 × 11 × 59 =
7,788
composite factor = 3 × 5 × 11 × 59 =
9,735
composite factor = 2
2 × 5 × 11 × 59 =
12,980
composite factor = 2
3 × 3 × 11 × 59 =
15,576
composite factor = 2 × 3 × 5 × 11 × 59 =
19,470
composite factor = 2
3 × 5 × 11 × 59 =
25,960
composite factor = 2
2 × 3 × 5 × 11 × 59 =
38,940
composite factor = 2
3 × 3 × 5 × 11 × 59 =
77,880
64 factors (divisors)
What times what is 77,880?
What number multiplied by what number equals 77,880?
All the combinations of any two natural numbers whose product equals 77,880.
1 × 77,880 = 77,880
2 × 38,940 = 77,880
3 × 25,960 = 77,880
4 × 19,470 = 77,880
5 × 15,576 = 77,880
6 × 12,980 = 77,880
8 × 9,735 = 77,880
10 × 7,788 = 77,880
11 × 7,080 = 77,880
12 × 6,490 = 77,880
15 × 5,192 = 77,880
20 × 3,894 = 77,880
22 × 3,540 = 77,880
24 × 3,245 = 77,880
30 × 2,596 = 77,880
33 × 2,360 = 77,880
40 × 1,947 = 77,880
44 × 1,770 = 77,880
55 × 1,416 = 77,880
59 × 1,320 = 77,880
60 × 1,298 = 77,880
66 × 1,180 = 77,880
88 × 885 = 77,880
110 × 708 = 77,880
118 × 660 = 77,880
120 × 649 = 77,880
132 × 590 = 77,880
165 × 472 = 77,880
177 × 440 = 77,880
220 × 354 = 77,880
236 × 330 = 77,880
264 × 295 = 77,880
32 unique multiplications The final answer:
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