21002220220221 has 12 divisors (see below), whose sum is σ = 30351869570880. Its totient is φ = 13994405107080.

The previous prime is 21002220220217. The next prime is 21002220220283. The reversal of 21002220220221 is 12202202220012.

21002220220221 is a `hidden beast` number, since 2 + 1 + 0 + 0 + 2 + 220 + 220 + 221 = 666.

It is not a de Polignac number, because 21002220220221 - 2² = 21002220220217 is a prime.

It is a super-3 number, since 3×21002220220221³ (a number of 41 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21002220220194 and 21002220220203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002220220621) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 589567845 + ... + 589603466.

It is an arithmetic number, because the mean of its divisors is an integer number (2529322464240).

Almost surely, 2^{21002220220221} is an apocalyptic number.

It is an amenable number.

21002220220221 is a deficient number, since it is larger than the sum of its proper divisors (9349649350659).

21002220220221 is a wasteful number, since it uses less digits than its factorization.

21002220220221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1179173296 (or 1179173293 counting only the distinct ones).

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

Adding to 21002220220221 its reverse (12202202220012), we get a palindrome (33204422440233).

The spelling of 21002220220221 in words is "twenty-one trillion, two billion, two hundred twenty million, two hundred twenty thousand, two hundred twenty-one".