The famous Russian oligarch Roman Abramovich had already liquidated and created at least 20 companies at the age of 25.
Abramovich was raised by his uncle, as the boy was orphaned. He opened his first business on the black market at 21, using money from his mother-in-law.
In the 1990s his business was already legal, and he opened and closed more than 20 companies.
What's interesting is that at 26, he was arrested for stealing government property. Despite this, at the age of 35 he was able to become governor of Chukotka. So far, the billionaire claims that he has done nothing illegal in his career.
The famous writer Joan Rowling came up with the idea to write a book about the wizard Harry Potter while she was riding the train.
She was 25 years old at the time. That same evening, Joan, who worked as an employee in the London office of Amnesty International, and began writing a children's book about the boy wizard.
She was inattentive at work, which got her fired. While writing the novel, she gave birth to a daughter, married and divorced.
And in 1995 the book was written, and two years later it was published.
Marissa Mayer, the head of Yahoo! was hired by Google as just a 20-something employee.
She was 24 years old at the time. She worked at the search engine for 13 years before becoming the CEO at Yahoo!
In April 1999, when Mayer joined Google, the company had just seven employees, all housed in one small room.
Cook and businesswoman Martha Stewart was a stockbroker at 25.
Before that, she worked as a model, advertising products from Chanel and Unilever. In 1972, Stewart became a homemaker and mother. One year later, she opened her own delivery and cooking company.
Mark Zuckerberg made his first profit with Facebook only when he had 300 million users.
When he was 25 years old, he had already been working on Facebook for 5 years. He was pleased with the result, but noted that this was just the beginning. And the very next year, Time named him "Man of the Year."
Sheryl Sandberg, Facebook's chief operating officer, just got her degree from Harvard at age 25.
Sandberg graduated from the university's economics department at age 25, after which she worked at the World Bank.
In 1995, she graduated from business school. And at the age of 29, she became a well-known chief of staff.
Famous businessman Richard Branson created his record company called Virgin Records.
At 20, Branson opened a music store, at 22 he was able to open a studio, and at 23 his own record company. This successful man made it an international firm by the time he was 30. Looking back, the British billionaire says those were truly difficult years. He worked seven days a week and hardly slept.
Howard Schultz - the head of Starbucks - worked as a regular salesman at Xerox.
At 26, he left to join Hammerplast. Then in Seattle, he happened to visit a Starbucks restaurant, and at 29, he went to work there. He is now the head of one of the largest chains of popular coffee shops in the world, Starbucks.
Jay Z was already a famous musician at the time, but for certain reasons he kept his anonymity.
Sean Corey Carter, known as Jay-Z, grew up in a poor neighborhood in Brooklyn, and began using his stage name at age 20. He maintained his anonymity until, at the age of 27, he and two friends founded the famous Roc-A-Fella Records record company. That same year he was able to release his first album Reasonable Doubt.