[lkirkwood]

Just nitpick but all odd numbers end in an odd number, not 1, and all even numbers end in an even number i.e. a multiple of 2.

[silisili]

Sure, but OP was talking about binary representation.

[dmichulke]

GP's statement is true for all number systems with an even base (so also for binary and decimal)

[Etheryte]

All odd numbers end in 1 in binary.