To find all the divisors of the number 15,243,990:
- 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 15,243,990:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
15,243,990 = 2 × 3 × 5 × 137 × 3,709
15,243,990 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 = (1 + 1) × (1 + 1) × (1 + 1) × (1 + 1) × (1 + 1) = 2 × 2 × 2 × 2 × 2 = 32
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 15,243,990
- Multiply the prime factors involved in the prime factorization of the number in all their unique combinations, that give different results.
- 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
prime factor =
5
composite factor = 2 × 3 =
6
composite factor = 2 × 5 =
10
composite factor = 3 × 5 =
15
composite factor = 2 × 3 × 5 =
30
prime factor =
137
composite factor = 2 × 137 =
274
composite factor = 3 × 137 =
411
composite factor = 5 × 137 =
685
composite factor = 2 × 3 × 137 =
822
composite factor = 2 × 5 × 137 =
1,370
composite factor = 3 × 5 × 137 =
2,055
prime factor =
3,709
This list continues below...
... This list continues from above
composite factor = 2 × 3 × 5 × 137 =
4,110
composite factor = 2 × 3,709 =
7,418
composite factor = 3 × 3,709 =
11,127
composite factor = 5 × 3,709 =
18,545
composite factor = 2 × 3 × 3,709 =
22,254
composite factor = 2 × 5 × 3,709 =
37,090
composite factor = 3 × 5 × 3,709 =
55,635
composite factor = 2 × 3 × 5 × 3,709 =
111,270
composite factor = 137 × 3,709 =
508,133
composite factor = 2 × 137 × 3,709 =
1,016,266
composite factor = 3 × 137 × 3,709 =
1,524,399
composite factor = 5 × 137 × 3,709 =
2,540,665
composite factor = 2 × 3 × 137 × 3,709 =
3,048,798
composite factor = 2 × 5 × 137 × 3,709 =
5,081,330
composite factor = 3 × 5 × 137 × 3,709 =
7,621,995
composite factor = 2 × 3 × 5 × 137 × 3,709 =
15,243,990
32 factors (divisors)
What times what is 15,243,990?
What number multiplied by what number equals 15,243,990?
All the combinations of any two natural numbers whose product equals 15,243,990.
1 × 15,243,990 = 15,243,990
2 × 7,621,995 = 15,243,990
3 × 5,081,330 = 15,243,990
5 × 3,048,798 = 15,243,990
6 × 2,540,665 = 15,243,990
10 × 1,524,399 = 15,243,990
15 × 1,016,266 = 15,243,990
30 × 508,133 = 15,243,990
137 × 111,270 = 15,243,990
274 × 55,635 = 15,243,990
411 × 37,090 = 15,243,990
685 × 22,254 = 15,243,990
822 × 18,545 = 15,243,990
1,370 × 11,127 = 15,243,990
2,055 × 7,418 = 15,243,990
3,709 × 4,110 = 15,243,990
16 unique multiplications The final answer:
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