311021020131221 has 4 divisors (see below), whose sum is σ = 311025245632032. Its totient is φ = 311016794630412.

The previous prime is 311021020131197. The next prime is 311021020131247. The reversal of 311021020131221 is 122131020120113.

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.

It is a cyclic number.

It is not a de Polignac number, because 311021020131221 - 2¹⁴ = 311021020114837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 311021020131193 and 311021020131202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311021020131421) 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, 2112639995 + ... + 2112787208.

It is an arithmetic number, because the mean of its divisors is an integer number (77756311408008).

Almost surely, 2^{311021020131221} is an apocalyptic number.

It is an amenable number.

311021020131221 is a deficient number, since it is larger than the sum of its proper divisors (4225500811).

311021020131221 is an equidigital number, since it uses as much as digits as its factorization.

311021020131221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4225500810.

The product of its (nonzero) digits is 144, while the sum is 20.

Adding to 311021020131221 its reverse (122131020120113), we get a palindrome (433152040251334).

The spelling of 311021020131221 in words is "three hundred eleven trillion, twenty-one billion, twenty million, one hundred thirty-one thousand, two hundred twenty-one".