The energy and waiting time distributions are important properties to understand the physical mechanism of repeating fast radio bursts (FRBs). Recently, Five-hundred-meter Aperture Spherical radio Telescope (FAST) detected the largest sample of FRB 121102, containing 1652 bursts. The energy distribution at high-energy range ($>10^{38}$ erg) can be fitted with a single power-law function with an index of $-1.86$. However, the distribution at low-energy range deviates from the power-law function. The energy distributions of high-energy bursts at different epochs are inconsistent. We find the power-law index of $-1.70$ for early bursts and $-2.60$ for later bursts. For bursts observed in a single day, a linear repetition pattern is found. We use the Weibull function to fit the waiting time distribution. The shape parameter $k = 0.72^{+0.01}_{-0.02}$ and the event rate $r = 734.47^{+29.04}_{-27.58}$ day$ ^{-1} $ are derived. If the waiting times with $delta_t < 28$ s are excluded, the burst behavior can be described by a Poisson process. The best-fitting values of $k$ are slightly different for low-energy and high-energy bursts. The event rates change significantly across the observing time, while the shape parameters $k$ vary slightly in different days.
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