Consider a continuous flight auger pile in a sandy soil deposit 10 m long with a diameter of 0.45 m. Following is the variation of standard penetration resistance values (N₆₀) with depth.

Depth (m) ................................... N₆₀
1.5 ................................................... 6
3.0 ................................................... 7
4.5 ................................................... 5
6.0 ................................................... 8
7.5 ................................................... 10
9.0 ................................................... 10
10.5 ................................................... 13
12.0 ................................................... 15
13.5 ................................................... 18
15.0 ................................................... 20
17.0 ................................................... 17
18.5 ................................................... 18
20.0 ................................................... 21

Estimate the ultimate load-carrying capacity of the pile. Assume unit weight of soil, γ = 15.5 kN/m³.