Abstract
We have investigated the stability of the orbital dynamics of a number of planets detected in binary star systems based on the analysis of data from the TESS orbital observatory. For 20 circumstellar planets we have obtained typical estimates of the Lyapunov time (the time of predictable dynamics). The secular orbital dynamics of 18 planets considered is stable with Lyapunov times greater than 6000 years. For the planets TOI-905b and TOI-1634b the calculated Lyapunov times (less than 3000 years) correspond to unstable dynamics and point to possible inaccuracies in the parameters of the planets found. A detailed analysis of the stability of the secular dynamics of the circumbinary planets TOI-1338 and TIC 172900988 has shown that on the stability diagrams the planets are located in regions with relatively large Lyapunov times (more than 7000 years), confirming the reliability of the derived parameters of the planets.