20020021021 has 32 divisors (see below), whose sum is σ = 26995707648. Its totient is φ = 14338045440.

The previous prime is 20020021019. The next prime is 20020021027. The reversal of 20020021021 is 12012002002.

It is a cyclic number.

It is not a de Polignac number, because 20020021021 - 2¹ = 20020021019 is a prime.

20020021021 is a modest number, since divided by 21021 gives 20020 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 20020020989 and 20020021007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20020021027) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 190315 + ... + 276151.

It is an arithmetic number, because the mean of its divisors is an integer number (843615864).

Almost surely, 2^20020021021 is an apocalyptic number.

It is an amenable number.

20020021021 is a deficient number, since it is larger than the sum of its proper divisors (6975686627).

20020021021 is a wasteful number, since it uses less digits than its factorization.

20020021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86101.

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 20020021021 its reverse (12012002002), we get a palindrome (32032023023).

The spelling of 20020021021 in words is "twenty billion, twenty million, twenty-one thousand, twenty-one".