21040222021 has 32 divisors (see below), whose sum is σ = 26355006720. Its totient is φ = 16354331136.

The previous prime is 21040221991. The next prime is 21040222039. The reversal of 21040222021 is 12022204012.

It is not a de Polignac number, because 21040222021 - 2⁷ = 21040221893 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21040221986 and 21040222004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21040222321) 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, 1263270 + ... + 1279816.

It is an arithmetic number, because the mean of its divisors is an integer number (823593960).

Almost surely, 2^21040222021 is an apocalyptic number.

It is an amenable number.

21040222021 is a deficient number, since it is larger than the sum of its proper divisors (5314784699).

21040222021 is a wasteful number, since it uses less digits than its factorization.

21040222021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16813.

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 21040222021 its reverse (12022204012), we get a palindrome (33062426033).

The spelling of 21040222021 in words is "twenty-one billion, forty million, two hundred twenty-two thousand, twenty-one".