Cutting insert, cutting tool, and method for manufacturing machined product

A cutting insert, comprising:

• a base comprising an upper side surface and a lower side surface;
• and
• a cutting part protruded from the base toward a first end,
• the cutting part comprises
• an upper surface extended from the upper side surface toward the first end,
• a first lateral surface which is located at a side of the first end and adjacent to the upper surface,
• a second lateral surface adjacent to the first lateral surface and the upper surface,
• a third lateral surface which is adjacent to the first lateral surface and the upper surface and which is located at a side opposite to the second lateral surface,
• a first ridgeline located on an intersection of the upper surface and the first lateral surface,
• a second ridgeline located on an intersection of the upper surface and the second lateral surface,
• a third ridgeline located on an intersection of the upper surface and the third lateral surface,
• a first cutting edge located on the first ridgeline, and
• a second cutting edge located on the second ridgeline, the upper surface comprises
• a first inclined surface located along the first ridgeline and inclined downward as going away from the first ridgeline,
• a pair of protrusions located side by side in a direction along the first ridgeline on the first inclined surface, and
• a first upheaved part located along the third ridgeline at a side further away from the first ridgeline than the pair of protrusions,
• the second cutting edge is inclined downward as going away from the first ridgeline, and
• an upper end of the first upheaved part is located above the second cutting edge.