311313332221 has 8 divisors (see below), whose sum is σ = 317195548344. Its totient is φ = 305431426560.

The previous prime is 311313332203. The next prime is 311313332249. The reversal of 311313332221 is 122233313113.

It can be written as a sum of positive squares in 4 ways, for example, as 91361712121 + 219951620100 = 302261^2 + 468990^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-311313332221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311313332261) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3426501 + ... + 3516181.

It is an arithmetic number, because the mean of its divisors is an integer number (39649443543).

Almost surely, 2^311313332221 is an apocalyptic number.

It is an amenable number.

311313332221 is a deficient number, since it is larger than the sum of its proper divisors (5882216123).

311313332221 is an equidigital number, since it uses as much as digits as its factorization.

311313332221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155231.

The product of its digits is 1944, while the sum is 25.

Adding to 311313332221 its reverse (122233313113), we get a palindrome (433546645334).

The spelling of 311313332221 in words is "three hundred eleven billion, three hundred thirteen million, three hundred thirty-two thousand, two hundred twenty-one".