Find the sum of even divisors of 4096.

• 4096 = 2^12
  
  sum of even divisors = 2^1+2^2+2^3+...+2^12 = (2^13-2)
• 10 years agoHelpfull: Yes(28) No(2)
• 2^1+2^2+2^4......+2^12
  the series is in geometric series....
  so the sum of g.m=a(r^n-1)/(r-1)
  a=first term
  r=common ratio..
  n=12
  since 4096=2^12
  a=2
  r=4
  ans=2^13-2
• 10 years agoHelpfull: Yes(7) No(6)
• first find out the divisors or factors of 4096 by taking LCM then all the factors like 2^12 then it will be written (2^0+2^1+2^2...+2^12)but when we have to find even divisors then eliminating 2^0 from above expression and sum up all the values and get ans as 8190.....
• 10 years agoHelpfull: Yes(6) No(0)
• rakesh plz explain
• 10 years agoHelpfull: Yes(2) No(1)
• sum of even divisors = 2^1+2^2+2^3+...+2^12 = 2^12
  by using sum of Gp
• 10 years agoHelpfull: Yes(2) No(2)
• 8190
  except 2^0(even divisors)
  2^1+.......+2^12
• 10 years agoHelpfull: Yes(1) No(1)
• 2^12=4096
  13 ans
  
• 10 years agoHelpfull: Yes(1) No(3)
• 4096/19=215
• 10 years agoHelpfull: Yes(0) No(6)
• it is a G.P.
  2,4,8,16,32....4096
  sum of G.P. is 4094=2^12-2
  
• 10 years agoHelpfull: Yes(0) No(1)
• Its factors are 2,4,8,16,32,64,128,256,512,1024,2048,4096. Howi calculated this?? firstly we have to find out the factors till half of the square divisor of 4096. Since 60*60=3600 and 70*70=4900 so we have to find factors till 60-70. So i started calculating from 2,2*2048, 4*1024, 8*512 since these all are factors in the form of powers of 2, i calculated all the factors by simple guessing.
• 10 years agoHelpfull: Yes(0) No(1)
• 4096=2^12
  even divisors are 2,4,8,16,32,64,128,256,512,1024,2048
  i.e. 2^1,2^2,2^3,2^4,2^5,2^6,2^7,2^8,2^9,2^10,2^11
  the sum of these numbers is: (2^12)-2 =4094
• 10 years agoHelpfull: Yes(0) No(2)
• the factors are 2^0,2^1,2^2,.....,2^12
  so sum o the factors will be 2^13-2
  
• 10 years agoHelpfull: Yes(0) No(2)
• what is the remainder when 48^565 divided by 7? todays my tcs question
  
• 10 years agoHelpfull: Yes(0) No(1)
• 4096=2^12
  so total number of factors will be 12+1=13
  so sum=2^13-2
• 10 years agoHelpfull: Yes(0) No(1)