I’m sorry, but I need more context or information to provide a specific answer as there are many individuals who could be considered a “math genius.” Please provide more details about who you are referring to.
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One person often associated with the title of “math genius” is Albert Einstein, who was not only a brilliant physicist but also an adept mathematician. In fact, many of his theories in physics were rooted in mathematical principles. A quote from Einstein on the topic of math is: “Pure mathematics is, in its way, the poetry of logical ideas.”
Here are some interesting facts about Einstein’s relationship with math:

At the age of 15, Einstein encountered a geometry book, which he later called his “holy geometry book.” He became so obsessed with the book that he taught himself all of its contents in just two years.

Einstein’s special theory of relativity, published in 1905, used mathematical equations to describe the relationship between space and time.

In 1915, Einstein published his general theory of relativity, which was based on complex mathematical equations and fundamentally changed the way we understand the universe.

Einstein is also known for his famous equation E=mc², which represents the relationship between energy and mass in physics.
While Einstein is certainly one notable “math genius,” there are countless individuals throughout history and today who have made significant contributions to the field. A table comparing some of the most famous mathematicians and their accomplishments could provide additional context for this nuanced question:
Mathematician  Accomplishments 

Pythagoras  Developed the Pythagorean theorem and founded the Pythagoreans 
Archimedes  Made advancements in calculus and geometry, credited with the Archimedes principle 
Isaac Newton  Developed calculus, laws of motion, and the law of universal gravitation 
Leonhard Euler  Made significant contributions to calculus and graph theory 
Ada Lovelace  Created the first computer program and is credited as one of the world’s first computer programmers 
Alan Turing  Famous for his work in codebreaking during World War II and developing the Turing machine, a precursor to modern computers 
Katherine Johnson  Helped calculate flight trajectories for NASA during the early space program, breaking barriers as a prominent African American woman in mathematics 
As we can see, the title of “math genius” can be applied to a diverse set of individuals with varying accomplishments and contributions to the field.
Response video to “Who is the math genius?”
Steve Harvey welcomes 8yearold math prodigy Miguel, from Florida, onto his show. Miguel shows off his skills by performing a math trick called the “fifth fruit” on Steve, where he is able to deduce the root of a number Steve is thinking of. Miguel claims that he first realized he was good at math when he was just two years old. Steve playfully jokes with Miguel, declaring him his son, and teasing that they will take a trip to Vegas together, with Miguel counting cards for Steve. The audience is left astounded by Miguel’s incredible math abilities.
I discovered more answers on the internet
Euler, Pythagoras, Ramanujan, and Fibonacci are all famous mathematical geniuses that come to our minds. Some of them, like Ramanujan, never went through any formal training in Mathematics and were selftaught which is mindblowing to the rest of us.
Gauss
Gauss was born on April 30, 1777 in a small German city north of the Harz mountains named Braunschweig. The son of peasant parents (both were illiterate), he developed a staggering number of important ideas and had many more named after him. Many have referred to him as the princeps mathematicorum, or the “ prince of mathematics.”
I was at least arguably pretty good at math. I was a math major, and I knew much more math than most of my peers, at least early in my education. In fairness, my main “weapon” probably wasn’t raw intellect or mathematical ability; instead, it was enthusiasm. I just liked math, so I spent a lot more time marinating in math than most people, even most math majors.
But even before all that, I was good at math in the more pedestrian sense — getting good grades on tests in high school without much (if any) studying… that sort of thing.
So what’s it like to be good at math? It’s not really like anything. I never really thought “wow, I’m good at math.” If anything, I only ever thought about other people “wow, how are you not getting this?”
Don’t get me wrong, I didn’t have as arrogant an attitude as that last sentence suggested. I understood the general fact of life that different people are good at different things. But I didn’t understand the mechanism of how someone could be bad at math…
More interesting questions on the issue
Who is the maths genius in the world?
Answer: Srinivasa Ramanujan
Srinivasa Ramanujan FRS  

Born  Srinivasa Ramanujan Aiyangar22 December 1887 Erode, Mysore State, British India (now in Tamil Nadu, India) 
Died  26 April 1920 (aged 32) Kumbakonam, Tanjore District, Madras Presidency, British India (now Thanjavur district, Tamil Nadu, India) 
Citizenship  British Indian 
Who is best at math in the world?
The response is: The highest cited scientist is Donald B. Rubin from Temple University with 309,479 citations.
Who is fastest math?
As a response to this: Did you know that the "World’s Fastest Human Calculator", a title that you’re probably hearing for the first time, is an Indian man? Born in Andhra Pradesh’s Eluru in 1999, Neelakantha Bhanu Prakash "is to math what Usain Bolt is to running," at least according to the BBC.
Who is a king of maths?
The response is: Ans: Srinivasa Ramanujan is known as the king of maths in India due to his contribution by working on the Analytical Theory of Numbers, Elliptical Function, and Infinite Series.
What makes a mathematical genius?
In reply to that: An early understanding of numbers may be a sign of mathematical ability. Oksana Kuzmina The film The Man Who Knew Infinity tells the gripping story of Srinivasa Ramanujan, an exceptionally talented, selftaught Indian mathematician.
What a graduate school recommendation was a mathematical genius?
Response to this: A graduate school recommendation was but one line: "HHe is a mathematical genius." The trajectory of his schizophrenia was unusual.
Are mathematical geniuses hypermentalistic?
But the lives of some mathematical geniuses seem to arc from mechanistic to mentalistic obsessions. Newton’s convictions about alchemy and astrology are hypermentalistic in that they imbue inanimate matter, from base metals to stars, with esoteric and messageladen properties.
Was Ramanujan a genius?
The reply will be: Littlewood was amazed by Ramanujan’s genius. After discussing the papers with Littlewood, Hardy concluded that the letters were "certainly the most remarkable I have received" and that Ramanujan was "a mathematician of the highest quality, a man of altogether exceptional originality and power".