312221231321 has 4 divisors (see below), whose sum is σ = 312225284532. Its totient is φ = 312217178112.

The previous prime is 312221231317. The next prime is 312221231323. The reversal of 312221231321 is 123132122213.

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 120433291225 + 191787940096 = 347035^2 + 437936^2 .

It is a cyclic number.

It is not a de Polignac number, because 312221231321 - 2² = 312221231317 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (312221231323) 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, 1908776 + ... + 2065881.

It is an arithmetic number, because the mean of its divisors is an integer number (78056321133).

Almost surely, 2^312221231321 is an apocalyptic number.

It is an amenable number.

312221231321 is a deficient number, since it is larger than the sum of its proper divisors (4053211).

312221231321 is an equidigital number, since it uses as much as digits as its factorization.

312221231321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4053210.

The product of its digits is 864, while the sum is 23.

Adding to 312221231321 its reverse (123132122213), we get a palindrome (435353353534).

The spelling of 312221231321 in words is "three hundred twelve billion, two hundred twenty-one million, two hundred thirty-one thousand, three hundred twenty-one".