If you add the top wing and the bottom wing of the AN-2 it's 106 feet. You did say prop plane, not motor glider (different class) or helicopter (different class).

Technical details
Wingspan: 59 ft 8 in (18.2 m) upper, 46 ft 9 in (14.2 m) lower
Length: 40 ft 8 in (12.4 m)
Maximum Takeoff Weight: 12,125 lb (5,500 kg)
Powerplant: 1 Shvetsov ASh-62R nine-cylinder supercharged radial engine, 1,000 hp (750 kW)- This unit was a license-built version of the Wright 'Cyclone' engine, as fitted to the Douglas DC-3 and many other aircraft of the 1930s, 40s and 50s.
Cruising Speed: 105 to 120 mph (170 to 190 km/h)
Range: 525 miles (845 km)
Service Ceiling: 14,750 feet (4.5 km)