日

日 X65E5 is Unicode character number 26085, KanjiLiberal, Nichi.

日 can be pronounced as たち (nichi) or び ("bi") and mean sun or day.
日 has many pronunciations and meanings, and is easy to confuse with other characters.

日 is described at Wictionary, https://en.wiktionary.org/wiki/日

Nichi

日 X65E5 is easy to confuse with other Nichi; all the four Nichi have similar graphic representations:

⽇ X2F47 , KanjiRadical

⽈ X2F48 , KanjiRadical

日 X65E5 , KanjiLiberal

曰 X66F0 , KanjiLiberal

In order to resolve the confusions, some programming is necessary.
The Utf8 encoding of each of the Nichi characters can be calculated by the PHP program du.t with command

php du.t ⽇⽈日曰

The output is

⽇⽈日曰
The array has 12 bytes; here is its splitting:
e2 bd 87 e2 bd 88 e6 97 a5 e6 9b b0
array(4) {
  [0]=>
  string(3) "⽇"
  [1]=>
  string(3) "⽈"
  [2]=>
  string(3) "日"
  [3]=>
  string(3) "曰"
}

Unicode character number 12103 id est, X2F47
Picture: ⽇ ; uses 3 bytes. These bytes are:
xE2 xBD x87 in the hexadecimal representation and
226 189 135 in the decimal representation

Unicode character number 12104 id est, X2F48
Picture: ⽈ ; uses 3 bytes. These bytes are:
xE2 xBD x88 in the hexadecimal representation and
226 189 136 in the decimal representation

Unicode character number 26085 id est, X65E5
Picture: 日 ; uses 3 bytes. These bytes are:
xE6 x97 xA5 in the hexadecimal representation and
230 151 165 in the decimal representation

Unicode character number 26352 id est, X66F0
Picture: 曰 ; uses 3 bytes. These bytes are:
xE6 x9B xB0 in the hexadecimal representation and
230 155 176 in the decimal representation

For year 2021, kanji 日 X65E5 seems to be most popular among other Nichi.

Wiktionary

Character 日 X65E5 is described at Wictionary.

The Japanese version https://ja.wiktionary.org/wiki/日 suggests the pronunciation and the semantics:

音読み
呉音: ニチ、ニッ
漢音: ジツ
訓読み
常用漢字表内
ひ、か
常用漢字表外
たち、す、こう、くさ、いる、あき、び、へ
(ひ、ニチ、ニッ)太陽。
日が昇る。日没
(ひ、ニッ)日光。日差し。
日に焼ける、日が差す、
(ひ、ニチ、ニッ、ジツ)地球が1周の自転をするのにかかる時間の単位。おもに平均太陽日。暦日。
半日
(ひ、ニチ、ニッ)太陽が観測できる時間帯。昼。
昼日中に、日中
(ひ、ニチ、ニッ、ジツ)特定の一日。
ひにち、祭日、日時
(ひ、ニチ、ニッ)日数。日々。
あれから日が経ったがまだ連絡がない。
日が浅い

The English version https://en.wiktionary.org/wiki/日 suggests definitions:

日
(astronomy) Sun
daytime; time between sunrise and sunset
日班 ― rìbān ― day shift
Antonyms: 夜 (yè), 夜間／夜间 (yèjiān), 夜晚 (yèwǎn), 晚上 (wǎnshang)
day; twenty-four hours
everyday; daily; day-to-day
day of the month
三月四日 ― sān yuè sì rì ― March 4
Synonym: 號／号 (hào)
some day; some other time
former times; previous times; the past
time; period; age
Classifier for days.
Short for 日本 (Rìběn, “Japan; Japanese; Nippo-”):
中日詞典 / 中日词典 ― zhōngrì cídiǎn ― Chinese-Japanese dictionary
(Beijing, Jiaoliao Mandarin, Southwestern Mandarin, Central Plains Mandarin, Jianghuai Mandarin, Lanyin Mandarin, dialectal Jin, dialectal Wu, dialectal Xiang, vulgar, often in abuses) to fuck; to have sexual intercourse with quotations ▼
狗日 ― gǒurì ― fucking
alt. forms: 入, 㒲, 肏
† Alternative form of 二 (èr, “two”).
(obsolete) Short for 日斯巴尼亞／日斯巴尼亚 (Rìsībāníyà, “Spain”).
(～母) (Chinese linguistics) the Middle Chinese initial of 日 (MC ȵiɪt̚)

The synonyms are suggested:
太陽 (“sun”)
白天 (“daytime”)
天 (“day (24 hours)”)
肏 (“to fuck; to have sex with”)

For year 2021, the same description (by the "redirect"), is suggested by the English Wictionary for character ⽇ X2F47, silently assuming, that these two characters mean the same.

Phonetic

日 has two main ways of pronunciation: ひ (hi) and にち (nichi).

Kotobabk

https://kotobank.jp/word/日-109713 日（読み）ヒ デジタル大辞泉「日」の解説

ひ【日】 １ （「陽」とも書く） ㋐太陽。日輪。おひさま。「日が昇る」「日が沈む」「日が傾く」 ㋑太陽の光線。日ざし。日光。「日がさす」「日に干す」「日に焼ける」
２ 日の出から日没までの間。ひるま。「日が長くなる」「日が暮れる」 ３ 地球が1回自転する間。二十四時間。一昼夜。「日に八時間働く」 ４ 日数。ひにち。「転居してまだ日が浅い」「日がたつ」 ..

にち【日】［漢字項目］ ［音］ニチ（呉）　ジツ（漢）　［訓］ひ　か ［学習漢字］1年 〈ニチ〉 １ 太陽。「日光・日食・日没・日輪」 ２ 昼間。「日中・日暮・日夜」 ..

Examples

週: use with 曜

Character 日 often appear after kanji 曜 (and sometimes also before it):

Key	Kanji	Hiragana	Romanji	English	meaning/mnenonic
月	月曜日	げつようび	getsuyoubi	Monday	Beginning
火	火曜日	かようび	kayoubi	Tuesday	Fire
水	水曜日	すいようび	Suiyoubi	Wednesday	Water
木	木曜日	もくようび	mokuyoubi	Thursday	Tree
金	金曜日	きんようび	kinyoubi	Friday	Gold
土	土曜日	どようび	doyoubi	Saturday	Ground
日	日曜日	にちようび	nichiyoubi	Sunday	Enjoy, relax

In the last line of the table, character 日 appears twice. First, it is pronounced as にち (nichi), and then, as び ("bi").

Confusion

References

Keywords

du.t, Japanese, Kanji, KanjiConfudal, KanjiLiberal, KanjiRadical, Nichi, PHP, ud.t, Unicode, Utf8, X2F47 ⽇, X2F48 ⽈, X65E5 日, X66F0 曰