And MANY of them, though not EVERYONE, grow up to be "weird" to the larger group of "normal people". They tend to live in their own world, turning everything into numbers in their heads. They maybe great with math, but MANY (again, not EVERRYONE) fail miserably in leading a "normal life".
Get ready for this genius, he maybe great for the development of science of human kind, but maybe a "headache" for parenting.
I hope, your son is a math genius and can also have a "normal" life as well.