20033404021 has 2 divisors, whose sum is σ = 20033404022. Its totient is φ = 20033404020.

The previous prime is 20033404019. The next prime is 20033404037. The reversal of 20033404021 is 12040433002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19854219025 + 179184996 = 140905^2 + 13386^2 .

It is a cyclic number.

It is not a de Polignac number, because 20033404021 - 2¹ = 20033404019 is a prime.

Together with 20033404019, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 20033404021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20033404621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10016702010 + 10016702011.

It is an arithmetic number, because the mean of its divisors is an integer number (10016702011).

Almost surely, 2^20033404021 is an apocalyptic number.

It is an amenable number.

20033404021 is a deficient number, since it is larger than the sum of its proper divisors (1).

20033404021 is an equidigital number, since it uses as much as digits as its factorization.

20033404021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 19.

Adding to 20033404021 its reverse (12040433002), we get a palindrome (32073837023).

The spelling of 20033404021 in words is "twenty billion, thirty-three million, four hundred four thousand, twenty-one".