Hey there!
1) To solve this, You have to know the Atbash cipher code. This code involves changing the alphabet backwards.
So,
A=Z
B=Y
C=X
D=W
E=V
F=U
G=T
H=S
I=R
J=Q
K=P
L=O
M=N
N=M
O=L
P=K
Q=J
R=I
S=H
T=G
U=F
V=E
W=D
X=C
Y=B
Z=A
So, if we use this code, the following letters: Blf xzm mvevi hloev z kilyovn lm gsv ovevo lm dsrxs rg dzh xivzgvw become: You can never solve a problem on the level on which it was created.
The answer to question 1 is: You can never solve a problem on the level on which it was created.
2) 1729 is considered as a magic number because 1729=1³+12³=9³+10³
These equal to the sum of the cubes of 2 unlike groups of numbers.
Thank you! :D