20320210021 has 4 divisors (see below), whose sum is σ = 20350404172. Its totient is φ = 20290015872.

The previous prime is 20320210019. The next prime is 20320210069. The reversal of 20320210021 is 12001202302.

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 5286017025 + 15034192996 = 72705^2 + 122614^2 .

It is a cyclic number.

It is not a de Polignac number, because 20320210021 - 2¹ = 20320210019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20320209983 and 20320210010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20320210091) 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 3 ways as a sum of consecutive naturals, for example, 15096066 + ... + 15097411.

It is an arithmetic number, because the mean of its divisors is an integer number (5087601043).

Almost surely, 2^20320210021 is an apocalyptic number.

It is an amenable number.

20320210021 is a deficient number, since it is larger than the sum of its proper divisors (30194151).

20320210021 is an equidigital number, since it uses as much as digits as its factorization.

20320210021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30194150.

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 20320210021 its reverse (12001202302), we get a palindrome (32321412323).

The spelling of 20320210021 in words is "twenty billion, three hundred twenty million, two hundred ten thousand, twenty-one".