400 is the natural number following 399 and preceding 401.
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Overview
400 (four hundred) is the natural number following 399 and preceding 401.
Mathematical properties
400 is the square of 20. 400 is the sum of the powers of 7 from 0 to 3, thus making it a repdigit in base 7 (1111).
A circle is divided into 400 grads, which is equal to 360 degrees and 2π radians. (Degrees and radians are the SI accepted units).
