Japanese number lore revolves around wordplay rooted in kanji readings. Some numbers are blessed by tradition โ like the Seven Lucky Gods โ while those that whisper of death or suffering are politely erased from hospital doors and gift counts.
When giving gifts in Japan, avoid sets of four or nine; odd numbers like 3, 5, and 7 are the safe, auspicious choice โ the same trio celebrated in the Shichi-Go-San children's festival.