Adding to 31213031202103 its reverse (30120213031213), we get a palindrome (61333244233316).
It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is a Duffinian number.
It is a congruent number.
Almost surely, 231213031202103 is an apocalyptic number.
31213031202103 is an equidigital number, since it uses as much as digits as its factorization.
31213031202103 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 441450176.
The spelling of 31213031202103 in words is "thirty-one trillion, two hundred thirteen billion, thirty-one million, two hundred two thousand, one hundred three".