21002222022021 has 24 divisors (see below), whose sum is σ = 30491434072320. Its totient is φ = 13930138879200.

The previous prime is 21002222022013. The next prime is 21002222022097. The reversal of 21002222022021 is 12022022220012.

It is not a de Polignac number, because 21002222022021 - 2³ = 21002222022013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21002222021985 and 21002222022003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002222022421) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4343385 + ... + 7801886.

It is an arithmetic number, because the mean of its divisors is an integer number (1270476419680).

Almost surely, 2^{21002222022021} is an apocalyptic number.

It is an amenable number.

21002222022021 is a deficient number, since it is larger than the sum of its proper divisors (9489212050299).

21002222022021 is a wasteful number, since it uses less digits than its factorization.

21002222022021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12146257 (or 12146254 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 21002222022021 its reverse (12022022220012), we get a palindrome (33024244242033).

The spelling of 21002222022021 in words is "twenty-one trillion, two billion, two hundred twenty-two million, twenty-two thousand, twenty-one".