21101222211021 has 12 divisors (see below), whose sum is σ = 30482762873472. Its totient is φ = 14065995467976.

The previous prime is 21101222211019. The next prime is 21101222211031. The reversal of 21101222211021 is 12011222210112.

21101222211021 is a `hidden beast` number, since 211 + 0 + 1 + 222 + 211 + 0 + 21 = 666.

It is not a de Polignac number, because 21101222211021 - 2¹ = 21101222211019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21101222210985 and 21101222211003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101222211031) 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, 123743901 + ... + 123914306.

It is an arithmetic number, because the mean of its divisors is an integer number (2540230239456).

Almost surely, 2^{21101222211021} is an apocalyptic number.

It is an amenable number.

21101222211021 is a deficient number, since it is larger than the sum of its proper divisors (9381540662451).

21101222211021 is a wasteful number, since it uses less digits than its factorization.

21101222211021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247667680 (or 247667677 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21101222211021 its reverse (12011222210112), we get a palindrome (33112444421133).

Subtracting from 21101222211021 its reverse (12011222210112), we obtain a palindrome (9090000000909).

The spelling of 21101222211021 in words is "twenty-one trillion, one hundred one billion, two hundred twenty-two million, two hundred eleven thousand, twenty-one".