I come from China, I like to talk my thought about 4 Billion issue, in China statutory measurement units , we will call the 4 billion is 40 yi (yi pronunciation is E (in A B C D E), and 40 is not so bad as 4 in China culture.
But i don't know other Asia issue about 4 billion.
if we still want change the quantity, I suggest the number 3.99 billion,because 3.99 billion =21 million*190.
and 21 million is bitcoin quantity, while 190 is a good number in China, it means live long, bitcoin*190 will means we can live longer than bitcoin.
The hate for 4 comes from the pronuncination of 4 (= 四 [sì]) is almost same with the pronunciation of death(=死[sǐ])
4 = 四 [sì]
40 = 四十 [sìshí]
40 includes 4 in pronunciation.
EDIT/
My hobby is banknote collecting.
The special serial no. banknote is expensive.
Solid number note(1111111, 2222222,.....9999999) is most expensive.
Among them, 8888888 is most expensive, and 4444444 is cheapest in spite of same rarity.
Million number note(1000000, 2000000,.....9000000) is expensive, too.
Among them, 8000000 is most expensive, and 4000000 is cheapest in spite of same rarity.
The love/hate for special number also influences on the price like this.