Atlanta Hawks owner Bruce Levenson abruptly announced he's selling the team because he's guilty of sending an email so racist ... it would make Donald Sterling cringe.

Levenson admits he sent the email to team execs back in 2012, urging them to get more suburban white fans at games. He then laid out all the problems with the current fan base, listing the following:

- it's 70 pct black
- the cheerleaders are black
- the music is hip hop
- at the bars it's 90 pct black
- there are few fathers and sons at the games
- the concerts [after games] are either hip hop or gospel

Levenson continued in the email ... "My theory is that the black crowd scared away the whites and there are simply not enough affluent black fans to build a significant  season ticket base." He also complained that he's told team execs, "I want some white cheerleaders ... I have even bitched that the kiss cam is too black."

NBA Commissioner Adam Silver says Levenson copped to the email in July -- about 2 months after Donald Sterling was banned -- and immediately informed the league he would sell the team.

Levenson apologized to fans in a statement, saying ... "If you're angry about what I wrote, you should be. I'm angry at myself too."

source: tmz.com