I have extracted the three rotation angles from a rotation matrix. Now if an object is multiplied by the rotation matrix or the rotation angles, both should give the same result. I followed the following order of rotation and I get the correct result, i.e. multiplying the object with the rotation matrix gives the same result:

glRotatef(y_rotation*180.0)/PI, 0.0, 1.0, 0.0);
glRotatef(z_rotation*180.0)/PI, 0.0, 0.0, 1.0);

glRotatef(x_rotation*180.0)/PI, 1.0, 0.0, 0.0);

Does it imply that OpenGL follows that order or it depends on how the original matrix multiplication is done.