31221231233 has 4 divisors (see below), whose sum is σ = 31265770068. Its totient is φ = 31176692400.

The previous prime is 31221231203. The next prime is 31221231241. The reversal of 31221231233 is 33213212213.

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 14927219329 + 16294011904 = 122177^2 + 127648^2 .

It is a cyclic number.

It is not a de Polignac number, because 31221231233 - 2²⁸ = 30952795777 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31221231199 and 31221231208.

It is not an unprimeable number, because it can be changed into a prime (31221231203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22268366 + ... + 22269767.

It is an arithmetic number, because the mean of its divisors is an integer number (7816442517).

Almost surely, 2^31221231233 is an apocalyptic number.

It is an amenable number.

31221231233 is a deficient number, since it is larger than the sum of its proper divisors (44538835).

31221231233 is an equidigital number, since it uses as much as digits as its factorization.

31221231233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44538834.

The product of its digits is 1296, while the sum is 23.

Adding to 31221231233 its reverse (33213212213), we get a palindrome (64434443446).

The spelling of 31221231233 in words is "thirty-one billion, two hundred twenty-one million, two hundred thirty-one thousand, two hundred thirty-three".