311223113221 has 4 divisors (see below), whose sum is σ = 311226183532. Its totient is φ = 311220042912.

The previous prime is 311223113197. The next prime is 311223113233. The reversal of 311223113221 is 122311322113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122311322113 = 29 ⋅4217631797.

It can be written as a sum of positive squares in 2 ways, for example, as 46781364100 + 264441749121 = 216290^2 + 514239^2 .

It is a cyclic number.

It is not a de Polignac number, because 311223113221 - 2¹⁹ = 311222588933 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 311223113192 and 311223113201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311223113021) 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, 1377726 + ... + 1587631.

It is an arithmetic number, because the mean of its divisors is an integer number (77806545883).

Almost surely, 2^311223113221 is an apocalyptic number.

It is an amenable number.

311223113221 is a deficient number, since it is larger than the sum of its proper divisors (3070311).

311223113221 is a wasteful number, since it uses less digits than its factorization.

311223113221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3070310.

The product of its digits is 432, while the sum is 22.

Adding to 311223113221 its reverse (122311322113), we get a palindrome (433534435334).

The spelling of 311223113221 in words is "three hundred eleven billion, two hundred twenty-three million, one hundred thirteen thousand, two hundred twenty-one".