-40 Degrees is the Temperature Where the Fahrenheit and Celsius Scales Meet (-40°F = -40°C)
Negative forty degrees is the temperature where the Fahrenheit and Celsius scales correspond with one another (-40°F = -40°C). Forty is also considered a semi-perfect number owing to the fact that a subset of its divisors added together gives 40 (i.e. 1, 4, 5, 10, and 20). Reference
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