21022021012221 has 32 divisors (see below), whose sum is σ = 31371269529600. Its totient is φ = 13912312431600.

The previous prime is 21022021012217. The next prime is 21022021012283. The reversal of 21022021012221 is 12221012022012.

It is a happy number.

21022021012221 is a `hidden beast` number, since 2 + 1 + 0 + 220 + 210 + 12 + 221 = 666.

It is not a de Polignac number, because 21022021012221 - 2² = 21022021012217 is a prime.

It is a super-2 number, since 2×21022021012221² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21022021012194 and 21022021012203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21022021012021) 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, 34037650 + ... + 34649756.

It is an arithmetic number, because the mean of its divisors is an integer number (980352172800).

Almost surely, 2^{21022021012221} is an apocalyptic number.

It is an amenable number.

21022021012221 is a deficient number, since it is larger than the sum of its proper divisors (10349248517379).

21022021012221 is a wasteful number, since it uses less digits than its factorization.

21022021012221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 621406 (or 621400 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21022021012221 its reverse (12221012022012), we get a palindrome (33243033034233).

The spelling of 21022021012221 in words is "twenty-one trillion, twenty-two billion, twenty-one million, twelve thousand, two hundred twenty-one".