While Kim Kardashian's husband, Kanye West, may be slightly biased in his assessment that his wife is more influential than even the first lady of the United States, it's difficult to argue with her social media profile. Add in Khloe, Kourtney and half sisters Kendall and Kylie, and the family's reach is a dream come true for any brand.
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"We only take on projects that we're really passionate about," Kourtney said. "We always say we are a brand for our fans because through social media we're so lucky to see what people are asking us for, what they're looking for and so we really design what we like but also take our fans in mind."
Kim has nearly 22 million followers on Twitter. (To put this in perspective, Beyonce Knowles has 13.4 million.) Kourtney has an impressive 12.1 million Twitter followers and Khloe has more than 10.1 million. On Facebook's Instagram, Kim's profile has nearly 16 million followers. On Sunday Kim posted a close-up picture of herself flashing her engagement ring with the hashtag "#goodmorning" and it got more than 622,000 "likes."
Is it possible to have too many product endorsements or partnerships in their empire? Kim said the sisters are careful about protecting their brand.
"Last year we really re-evaluated what our brand is and what it stands for and we stopped putting our name on things. We really wanted to only be involved in ...things we're extremely passionate about and something that we own," Kim said.
Having children, she said, caused her to re-prioritize her life. However, she disagreed with PepsiCo CEO Indra Nooyi's comments that women can't have it all.
"That's just not like a positive outlook. For me, like, my mom taught us girls we could have it all," Kim said.
—By CNBC's Courtney Reagan; Michelle Fox contributed to this report.