21222101022021 has 6 divisors (see below), whose sum is σ = 30654145920710. Its totient is φ = 14148067348008.

The previous prime is 21222101022013. The next prime is 21222101022079. The reversal of 21222101022021 is 12022010122212.

It is a happy number.

21222101022021 is a `hidden beast` number, since 212 + 2 + 210 + 1 + 0 + 220 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 19146444192225 + 2075656829796 = 4375665^2 + 1440714^2 .

It is not a de Polignac number, because 21222101022021 - 2³ = 21222101022013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21222101021985 and 21222101022003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222101029021) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1179005612326 + ... + 1179005612343.

Almost surely, 2^{21222101022021} is an apocalyptic number.

It is an amenable number.

21222101022021 is a deficient number, since it is larger than the sum of its proper divisors (9432044898689).

21222101022021 is a wasteful number, since it uses less digits than its factorization.

21222101022021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2358011224675 (or 2358011224672 counting only the distinct ones).

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

Adding to 21222101022021 its reverse (12022010122212), we get a palindrome (33244111144233).

The spelling of 21222101022021 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred one million, twenty-two thousand, twenty-one".