Permanent magnet and permanent magnet powder

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A permanent magnet includes R and T (R essentially includes Sm one or more of rare earth elements in addition to Sm, and T essentially includes Fe, or Fe and Co, one or more of transition metal elements in addition to Fe, or Fe and Co). A composition ratio of R in the permanent magnet is 20 at % or more and 40 at % or less. A remaining part is substantially only T, or only T and C. T amount is more than 1.5 times of R amount and less than 4.0 times of the R amount. Main phase grains included in the permanent magnet have an Nd5Fe17 type crystal structure. An average crystal grain size of the main phase grains of the permanent magnet is greater than 1 μm. A number ratio of main phase grains having a crystal grain size of less than 0.4 μm is less than 20%.