311244305221 has 4 divisors (see below), whose sum is σ = 321976867500. Its totient is φ = 300511742944.

The previous prime is 311244305209. The next prime is 311244305243. The reversal of 311244305221 is 122503442113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122503442113 = 13 ⋅9423341701.

It can be written as a sum of positive squares in 2 ways, for example, as 210984048900 + 100260256321 = 459330^2 + 316639^2 .

It is a cyclic number.

It is not a de Polignac number, because 311244305221 - 2⁵ = 311244305189 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 311244305221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311244305261) 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, 5366281096 + ... + 5366281153.

It is an arithmetic number, because the mean of its divisors is an integer number (80494216875).

Almost surely, 2^311244305221 is an apocalyptic number.

It is an amenable number.

311244305221 is a deficient number, since it is larger than the sum of its proper divisors (10732562279).

311244305221 is a wasteful number, since it uses less digits than its factorization.

311244305221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10732562278.

The product of its (nonzero) digits is 5760, while the sum is 28.

Adding to 311244305221 its reverse (122503442113), we get a palindrome (433747747334).

The spelling of 311244305221 in words is "three hundred eleven billion, two hundred forty-four million, three hundred five thousand, two hundred twenty-one".