Amazing number

An amazing number is name for such even number, the decomposition product of prime numbers has exactly three not necessarily different factors and the sum of all its divisors is equal to twice that number. Find all amazing numbers.

Result

n =  28

Solution:

Solution in text n =

Try another example






Leave us a comment of example and its solution (i.e. if it is still somewhat unclear...):

Showing 0 comments:
1st comment
Be the first to comment!
avatar




To solve this example are needed these knowledge from mathematics:

Next similar examples:

  1. Unknown number
    unknown Unknown number is divisible by exactly three different primes. When we compare these primes in ascending order, the following applies: • Difference first and second prime number is half the difference between the third and second prime numbers. • The produ
  2. Combinations
    circles How many different combinations of two-digit number divisible by 4 arises from the digits 3, 5 and 7?
  3. Numbers
    primes Write smallest three-digit number, which in division 5 and 7 gives the rest 2.
  4. Chebyshev formula
    ChebyshevSpiral To estimate the number of primes less than x is used Chebyshev formula: ? Estimate the number of primes less than 30300537.
  5. Divisors
    divisors The sum of all divisors unknown odd number is 2112. Determine sum of all divisors of number which is twice of unknown numbers.
  6. Theorem prove
    thales_1 We want to prove the sentense: If the natural number n is divisible by six, then n is divisible by three. From what assumption we started?
  7. Teams
    football_team How many ways can divide 16 players into two teams of 8 member?
  8. Blocks
    cubes3_1 There are 9 interactive basic building blocks of an organization. How many two-blocks combinations are there?
  9. Examination
    examination The class is 21 students. How many ways can choose two to examination?
  10. Confectionery
    cukrovinky The village markets have 5 kinds of sweets, one weighs 31 grams. How many different ways a customer can buy 1.519 kg sweets.
  11. PIN - codes
    pin How many five-digit PIN - code can we create using the even numbers?
  12. Average
    chart If the average(arithmetic mean) of three numbers x,y,z is 50. What is the average of there numbers (3x +10), (3y +10), (3z+10) ?
  13. Line
    skew_lines It is true that the lines that do not intersect are parallel?
  14. Sequence
    seq_1 Write the first 6 members of these sequence: a1 = 5 a2 = 7 an+2 = an+1 +2 an
  15. Reference angle
    anglemeter Find the reference angle of each angle:
  16. Trigonometry
    sinus Is true equality? ?
  17. Legs
    rak Cancer has 5 pairs of legs. The insect has 6 legs. 60 animals have a total of 500 legs. How much more are cancers than insects?