亿 yì 100,000,000; hundred million
Made up of [亻 rén Person (radical) radical 9, 乚 yǐ hidden; concealed; small radical 5]Alternative traditional form of character: 億
Made with 18 strokes.
Combination of 'person' and phonetic for 'yi' the connection with such a large number is not clear, may be just a suggestion of the population as a whole
Ancient small seal form 
Related characters
Also uses 亻 rén component: 俩 bǐng (both) 倡 chàng (to initiate) 代 dài (replace) 但 dàn (but) 倒 dào (fall) 仿 fǎng (to imitate) 份 fèn (portion) 供 gōng (to provide) 估 gū (estimate) 何 hé (what) 候 hòu (wait) 侯 hóu (nobleman) 化 huà (to make into) 华 huá (splendid) 花 huā (flower) 健 jiàn (healthy) 两 liǎng (pair) 们 mén (s) 你 nǐ (you) 仁 rén (humane) 什 shén (what) 他 tā (he) 位 wèi (position) 仙 xiān (immortal) 信 xìn (letter) 夜 yè (night) 攸 yōu (distant) 值 zhí (value) 住 zhù (to live) 传 zhuàn (biography) 作 zuò (to do) 做 zuò (to make)
Also uses 乚 yǐ component: 吃 chī (to eat) 曷 hé (why) 九 jiǔ (nine) 孔 kǒng (great) 礼 lǐ (ceremony) 令 lìng (to order) 乱 luàn (in confusion or disorder) 卖 mài (sell) 买 mǎi (buy) 习 xí (to practice) 也 yě (also) 艺 yì (skill) 忆 yì (to recollect) 以 yǐ (to use)
Sounds same
易 yì (easy) 益 yì 义 yì (justice) 亦 yì (also) 邑 yì (city) 弋 yì (catch) 艺 yì (skill) 忆 yì (to recollect) 意 yì (idea) 异 yì (different)Different tone
一 yī (one) 医 yī (doctor) 衤 yī (clothes) 衣 yī (clothes) 颐 yí 宜 yí (proper) 夷 yí (barbarians) 乚 yǐ (hidden) 以 yǐ (to use) 椅 yǐ (chair) 已 yǐ (already) 乙 yǐ (twist)Pronunciation
Sound file kindly provided by shtooka.net ➚ under a Creative Commons Attribution Share Alike License
Stroke order for character 亿, kindly provided under Wikimedia creative commons license ➚