21022121000221 has 64 divisors (see below), whose sum is σ = 24514498658304. Its totient is φ = 17849853964800.

The previous prime is 21022121000117. The next prime is 21022121000249. The reversal of 21022121000221 is 12200012122012.

It is a happy number.

It is not a de Polignac number, because 21022121000221 - 2¹⁵ = 21022120967453 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21022121000195 and 21022121000204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21022121000521) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 505282206 + ... + 505323808.

It is an arithmetic number, because the mean of its divisors is an integer number (383039041536).

Almost surely, 2^{21022121000221} is an apocalyptic number.

It is an amenable number.

21022121000221 is a deficient number, since it is larger than the sum of its proper divisors (3492377658083).

21022121000221 is a wasteful number, since it uses less digits than its factorization.

21022121000221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42154.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21022121000221 its reverse (12200012122012), we get a palindrome (33222133122233).

The spelling of 21022121000221 in words is "twenty-one trillion, twenty-two billion, one hundred twenty-one million, two hundred twenty-one", and thus it is an aban number.