31212131031313 has 4 divisors (see below), whose sum is σ = 31216747534308. Its totient is φ = 31207514528320.

The previous prime is 31212131031259. The next prime is 31212131031337. The reversal of 31212131031313 is 31313013121213.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15110145029329 + 16101986001984 = 3887177^2 + 4012728^2 .

It is a cyclic number.

It is not a de Polignac number, because 31212131031313 - 2²⁵ = 31212097476881 is a prime.

It is a super-4 number, since 4×31212131031313⁴ (a number of 55 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31212131031343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2308241356 + ... + 2308254877.

It is an arithmetic number, because the mean of its divisors is an integer number (7804186883577).

Almost surely, 2^{31212131031313} is an apocalyptic number.

It is an amenable number.

31212131031313 is a deficient number, since it is larger than the sum of its proper divisors (4616502995).

31212131031313 is an equidigital number, since it uses as much as digits as its factorization.

31212131031313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4616502994.

The product of its (nonzero) digits is 972, while the sum is 25.

Adding to 31212131031313 its reverse (31313013121213), we get a palindrome (62525144152526).

The spelling of 31212131031313 in words is "thirty-one trillion, two hundred twelve billion, one hundred thirty-one million, thirty-one thousand, three hundred thirteen".