21000220002021 has 32 divisors (see below), whose sum is σ = 30376108255360. Its totient is φ = 12828123187200.

The previous prime is 21000220001951. The next prime is 21000220002029. The reversal of 21000220002021 is 12020002200012.

It is not a de Polignac number, because 21000220002021 - 2¹¹ = 21000219999973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21000220001988 and 21000220002006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000220002029) 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, 32865501 + ... + 33498381.

It is an arithmetic number, because the mean of its divisors is an integer number (949253382980).

Almost surely, 2^{21000220002021} is an apocalyptic number.

It is an amenable number.

21000220002021 is a deficient number, since it is larger than the sum of its proper divisors (9375888253339).

21000220002021 is a wasteful number, since it uses less digits than its factorization.

21000220002021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 639157.

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21000220002021 its reverse (12020002200012), we get a palindrome (33020222202033).

The spelling of 21000220002021 in words is "twenty-one trillion, two hundred twenty million, two thousand, twenty-one".