when was it first used?
The first known system with place value was the Mesopotamian base 60 system (c. 3400 BC).
Number
The first known system with place value was the Mesopotamian base 60 system (c. 3400 BC) 
what is parity of zero? It is the quality of an integer (zero) being even or odd. Zero has the parity of even. why is zero even? Because it shares all the properties that characterize even numbers. what is a number? A mathematical object used to count, measure, and label.
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Number [SEP] First use of numbers
Bones and other artifacts have been discovered with marks cut into them that many believe are tally marks. These tally marks may have been used for counting elapsed time, such as numbers of days, lunar cycles or keeping records of quantities, such as of animals. A tallying system has no concept of place value (as in modern decimal notation), which limits its representation of large numbers. Nonetheless tallying systems are considered the first kind of abstract numeral system. The first known system with place value was the Mesopotamian base 60 system (c. 3400 BC) and the earliest known base 10 system dates to 3100 BC in Egypt.