Imaging lens and imaging apparatus equipped with the imaging lens

An imaging lens comprising:

• in order from an object side of the imaging lens, a first lens group including a biconcave lens;
• a second lens group including two lenses whose convex surfaces are arranged opposite to each other, the second lens group having a positive refractive power as a whole;
• a third lens group including a biconcave lens;
• and
• a fourth lens group including two lenses whose convex surfaces are arranged opposite to each other, the fourth lens group having positive refractive power, as a whole,
• the imaging lens satisfying conditional expressions (1) and (2):
• 0.20<BF/L<0.44 (1)
• N4>1.8 (2)
• wherein BF represents a back focal length BF of the imaging lens, L represents a length L in a optical axial direction from a surface of the imaging lens nearest to an object to a surface of the imaging lens nearest to an image, and N4 represents a refractive index of the third lens group at the d-line,
• wherein each of the convex surfaces of the fourth lens group has a radius of curvature whose absolute value is smaller than that of the other surface of each lens.