20312221321 has 6 divisors (see below), whose sum is σ = 23628502410. Its totient is φ = 17410475376.

The previous prime is 20312221309. The next prime is 20312221351. The reversal of 20312221321 is 12312221302.

It can be written as a sum of positive squares in only one way, i.e., 10844931321 + 9467290000 = 104139^2 + 97300^2 .

It is not a de Polignac number, because 20312221321 - 2⁵ = 20312221289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20312221351) 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 5 ways as a sum of consecutive naturals, for example, 207267516 + ... + 207267613.

It is an arithmetic number, because the mean of its divisors is an integer number (3938083735).

Almost surely, 2^20312221321 is an apocalyptic number.

It is an amenable number.

20312221321 is a deficient number, since it is larger than the sum of its proper divisors (3316281089).

20312221321 is an equidigital number, since it uses as much as digits as its factorization.

20312221321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 414535143 (or 414535136 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

Subtracting from 20312221321 its sum of digits (19), we obtain a palindrome (20312221302).

Adding to 20312221321 its reverse (12312221302), we get a palindrome (32624442623).

The spelling of 20312221321 in words is "twenty billion, three hundred twelve million, two hundred twenty-one thousand, three hundred twenty-one".