From 1996 to 2021 time-series photoelectric photometry of the M1 -M2Ia-Iab red supergiant Betelgeuse was conducted using a wide-band V-filter centered on λ555 nm and narrow to intermediate-band Wing near infrared (NIR) titanium oxide (TiO) filters centered on λ719 nm, λ754 nm， and λl024 nm. The observations were made to continually monitor magnitude variations for periodicities and variable amplitudes, calculate seasonal changes of effective temperatures, size, and luminosities, and subsequently examine the interrelationships among these physical properties. Using the V-band observations, short- and long-term dominant periods of 439±5 and 2209±183 days， respectively， were found. Effective temperatures varied from 3528 K to 3731 K， and using an adopted distance of 197 PC, luminosities varied from 70564 L_⊙ to 114204L_⊙. Using these estimated values of effective temperature and luminosity, calculated radii, assuming spherical symmetry, varied from 710R_⊙ to 847R_⊙. NIR to V-band flux ratios indicate that Betelgeuse radiates, on the average, ~10 to ~20 times more in the NIR bands than the visual band. After NIR magnitude conversions from λl024 nm to λl040 nm， a surprising result was that the λ754-nm/λl040-nm flux ratio was nearly 1.0, indicating the bolometric magnitude can be approximated at the shorter wavelength (λ754 nm) magnitude in addition to the theoretically-thought longer (λ1040 nm) wavelength magnitude.
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