311311113221 has 4 divisors (see below), whose sum is σ = 318904067244. Its totient is φ = 303718159200.

The previous prime is 311311113187. The next prime is 311311113251. The reversal of 311311113221 is 122311113113.

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 9261945121 + 302049168100 = 96239^2 + 549590^2 .

It is a cyclic number.

It is not a de Polignac number, because 311311113221 - 2¹⁰ = 311311112197 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 311311113193 and 311311113202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311311113251) 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, 3796476950 + ... + 3796477031.

It is an arithmetic number, because the mean of its divisors is an integer number (79726016811).

Almost surely, 2^311311113221 is an apocalyptic number.

It is an amenable number.

311311113221 is a deficient number, since it is larger than the sum of its proper divisors (7592954023).

311311113221 is an equidigital number, since it uses as much as digits as its factorization.

311311113221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7592954022.

The product of its digits is 108, while the sum is 20.

Subtracting from 311311113221 its product of digits (108), we obtain a palindrome (311311113113).

Adding to 311311113221 its reverse (122311113113), we get a palindrome (433622226334).

The spelling of 311311113221 in words is "three hundred eleven billion, three hundred eleven million, one hundred thirteen thousand, two hundred twenty-one".