311203313221 has 4 divisors (see below), whose sum is σ = 311456119744. Its totient is φ = 310950506700.

The previous prime is 311203313219. The next prime is 311203313261. The reversal of 311203313221 is 122313302113.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 122313302113 = 79 ⋅1548269647.

It is a cyclic number.

It is not a de Polignac number, because 311203313221 - 2¹ = 311203313219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 311203313192 and 311203313201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311203313261) 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, 126401415 + ... + 126403876.

It is an arithmetic number, because the mean of its divisors is an integer number (77864029936).

Almost surely, 2^311203313221 is an apocalyptic number.

It is an amenable number.

311203313221 is a deficient number, since it is larger than the sum of its proper divisors (252806523).

311203313221 is a wasteful number, since it uses less digits than its factorization.

311203313221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252806522.

The product of its (nonzero) digits is 648, while the sum is 22.

Adding to 311203313221 its reverse (122313302113), we get a palindrome (433516615334).

The spelling of 311203313221 in words is "three hundred eleven billion, two hundred three million, three hundred thirteen thousand, two hundred twenty-one".