31222312321 has 4 divisors (see below), whose sum is σ = 31225904452. Its totient is φ = 31218720192.

The previous prime is 31222312313. The next prime is 31222312351. The reversal of 31222312321 is 12321322213.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12321322213 = 6569 ⋅1875677.

It can be written as a sum of positive squares in 2 ways, for example, as 27909043600 + 3313268721 = 167060^2 + 57561^2 .

It is a cyclic number.

It is not a de Polignac number, because 31222312321 - 2³ = 31222312313 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31222312292 and 31222312301.

It is not an unprimeable number, because it can be changed into a prime (31222312351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1782996 + ... + 1800421.

It is an arithmetic number, because the mean of its divisors is an integer number (7806476113).

Almost surely, 2^31222312321 is an apocalyptic number.

It is an amenable number.

31222312321 is a deficient number, since it is larger than the sum of its proper divisors (3592131).

31222312321 is an equidigital number, since it uses as much as digits as its factorization.

31222312321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3592130.

The product of its digits is 864, while the sum is 22.

Adding to 31222312321 its reverse (12321322213), we get a palindrome (43543634534).

The spelling of 31222312321 in words is "thirty-one billion, two hundred twenty-two million, three hundred twelve thousand, three hundred twenty-one".