the largest number representable in 1 bit is any number (including +infinity and beyond).
This article describing various Rube Goldberg machines, there is no need to agree on different ways of representing numbers when one can set a single bit to 1 to represent any desired pre-defined number, or 0 to represent its absence (or the number 0).
This is certainly pragmatic, although it breaks the math
q type size q literal forms underlying integer value (encoding)
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short (h) 16-bit 0Nh / -0Wh / 0Wh null = -32768; -inf = -32767; +inf = 32767
int (i) 32-bit 0Ni / -0Wi / 0Wi null = -2147483648; -inf = -2147483647; +inf = 2147483647
long (j) 64-bit 0N (or 0Nj) / -0W (or -0Wj) / 0W (or 0Wj) null = -9223372036854775808; -inf = -9223372036854775807; +inf = 9223372036854775807
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