To find all the divisors of the number 1,207,920:
- 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 1,207,920:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
1,207,920 = 24 × 3 × 5 × 7 × 719
1,207,920 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 1,207,920
- 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
prime factor =
7
composite factor = 2
3 =
8
composite factor = 2 × 5 =
10
composite factor = 2
2 × 3 =
12
composite factor = 2 × 7 =
14
composite factor = 3 × 5 =
15
composite factor = 2
4 =
16
composite factor = 2
2 × 5 =
20
composite factor = 3 × 7 =
21
composite factor = 2
3 × 3 =
24
composite factor = 2
2 × 7 =
28
composite factor = 2 × 3 × 5 =
30
composite factor = 5 × 7 =
35
composite factor = 2
3 × 5 =
40
composite factor = 2 × 3 × 7 =
42
composite factor = 2
4 × 3 =
48
composite factor = 2
3 × 7 =
56
composite factor = 2
2 × 3 × 5 =
60
composite factor = 2 × 5 × 7 =
70
composite factor = 2
4 × 5 =
80
composite factor = 2
2 × 3 × 7 =
84
composite factor = 3 × 5 × 7 =
105
composite factor = 2
4 × 7 =
112
composite factor = 2
3 × 3 × 5 =
120
composite factor = 2
2 × 5 × 7 =
140
composite factor = 2
3 × 3 × 7 =
168
composite factor = 2 × 3 × 5 × 7 =
210
composite factor = 2
4 × 3 × 5 =
240
composite factor = 2
3 × 5 × 7 =
280
composite factor = 2
4 × 3 × 7 =
336
composite factor = 2
2 × 3 × 5 × 7 =
420
composite factor = 2
4 × 5 × 7 =
560
prime factor =
719
composite factor = 2
3 × 3 × 5 × 7 =
840
This list continues below...
... This list continues from above
composite factor = 2 × 719 =
1,438
composite factor = 2
4 × 3 × 5 × 7 =
1,680
composite factor = 3 × 719 =
2,157
composite factor = 2
2 × 719 =
2,876
composite factor = 5 × 719 =
3,595
composite factor = 2 × 3 × 719 =
4,314
composite factor = 7 × 719 =
5,033
composite factor = 2
3 × 719 =
5,752
composite factor = 2 × 5 × 719 =
7,190
composite factor = 2
2 × 3 × 719 =
8,628
composite factor = 2 × 7 × 719 =
10,066
composite factor = 3 × 5 × 719 =
10,785
composite factor = 2
4 × 719 =
11,504
composite factor = 2
2 × 5 × 719 =
14,380
composite factor = 3 × 7 × 719 =
15,099
composite factor = 2
3 × 3 × 719 =
17,256
composite factor = 2
2 × 7 × 719 =
20,132
composite factor = 2 × 3 × 5 × 719 =
21,570
composite factor = 5 × 7 × 719 =
25,165
composite factor = 2
3 × 5 × 719 =
28,760
composite factor = 2 × 3 × 7 × 719 =
30,198
composite factor = 2
4 × 3 × 719 =
34,512
composite factor = 2
3 × 7 × 719 =
40,264
composite factor = 2
2 × 3 × 5 × 719 =
43,140
composite factor = 2 × 5 × 7 × 719 =
50,330
composite factor = 2
4 × 5 × 719 =
57,520
composite factor = 2
2 × 3 × 7 × 719 =
60,396
composite factor = 3 × 5 × 7 × 719 =
75,495
composite factor = 2
4 × 7 × 719 =
80,528
composite factor = 2
3 × 3 × 5 × 719 =
86,280
composite factor = 2
2 × 5 × 7 × 719 =
100,660
composite factor = 2
3 × 3 × 7 × 719 =
120,792
composite factor = 2 × 3 × 5 × 7 × 719 =
150,990
composite factor = 2
4 × 3 × 5 × 719 =
172,560
composite factor = 2
3 × 5 × 7 × 719 =
201,320
composite factor = 2
4 × 3 × 7 × 719 =
241,584
composite factor = 2
2 × 3 × 5 × 7 × 719 =
301,980
composite factor = 2
4 × 5 × 7 × 719 =
402,640
composite factor = 2
3 × 3 × 5 × 7 × 719 =
603,960
composite factor = 2
4 × 3 × 5 × 7 × 719 =
1,207,920
80 factors (divisors)
What times what is 1,207,920?
What number multiplied by what number equals 1,207,920?
All the combinations of any two natural numbers whose product equals 1,207,920.
1 × 1,207,920 = 1,207,920
2 × 603,960 = 1,207,920
3 × 402,640 = 1,207,920
4 × 301,980 = 1,207,920
5 × 241,584 = 1,207,920
6 × 201,320 = 1,207,920
7 × 172,560 = 1,207,920
8 × 150,990 = 1,207,920
10 × 120,792 = 1,207,920
12 × 100,660 = 1,207,920
14 × 86,280 = 1,207,920
15 × 80,528 = 1,207,920
16 × 75,495 = 1,207,920
20 × 60,396 = 1,207,920
21 × 57,520 = 1,207,920
24 × 50,330 = 1,207,920
28 × 43,140 = 1,207,920
30 × 40,264 = 1,207,920
35 × 34,512 = 1,207,920
40 × 30,198 = 1,207,920
42 × 28,760 = 1,207,920
48 × 25,165 = 1,207,920
56 × 21,570 = 1,207,920
60 × 20,132 = 1,207,920
70 × 17,256 = 1,207,920
80 × 15,099 = 1,207,920
84 × 14,380 = 1,207,920
105 × 11,504 = 1,207,920
112 × 10,785 = 1,207,920
120 × 10,066 = 1,207,920
140 × 8,628 = 1,207,920
168 × 7,190 = 1,207,920
210 × 5,752 = 1,207,920
240 × 5,033 = 1,207,920
280 × 4,314 = 1,207,920
336 × 3,595 = 1,207,920
420 × 2,876 = 1,207,920
560 × 2,157 = 1,207,920
719 × 1,680 = 1,207,920
840 × 1,438 = 1,207,920
40 unique multiplications The final answer:
(scroll down)