31213220323 has 4 divisors (see below), whose sum is σ = 31218931008. Its totient is φ = 31207509640.

The previous prime is 31213220321. The next prime is 31213220329. The reversal of 31213220323 is 32302231213.

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

It is a cyclic number.

It is not a de Polignac number, because 31213220323 - 2¹ = 31213220321 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31213220294 and 31213220303.

It is not an unprimeable number, because it can be changed into a prime (31213220321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2847136 + ... + 2858077.

It is an arithmetic number, because the mean of its divisors is an integer number (7804732752).

Almost surely, 2^31213220323 is an apocalyptic number.

31213220323 is a deficient number, since it is larger than the sum of its proper divisors (5710685).

31213220323 is an equidigital number, since it uses as much as digits as its factorization.

31213220323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5710684.

The product of its (nonzero) digits is 1296, while the sum is 22.

Adding to 31213220323 its reverse (32302231213), we get a palindrome (63515451536).

The spelling of 31213220323 in words is "thirty-one billion, two hundred thirteen million, two hundred twenty thousand, three hundred twenty-three".