21021101102221 has 32 divisors (see below), whose sum is σ = 24324617520000. Its totient is φ = 17983956480000.

The previous prime is 21021101102219. The next prime is 21021101102297. The reversal of 21021101102221 is 12220110112012.

It is a cyclic number.

It is not a de Polignac number, because 21021101102221 - 2¹ = 21021101102219 is a prime.

It is a super-2 number, since 2×21021101102221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21021101102195 and 21021101102204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021101102021) 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, 12981405 + ... + 14510653.

It is an arithmetic number, because the mean of its divisors is an integer number (760144297500).

Almost surely, 2^{21021101102221} is an apocalyptic number.

It is an amenable number.

21021101102221 is a deficient number, since it is larger than the sum of its proper divisors (3303516417779).

21021101102221 is a wasteful number, since it uses less digits than its factorization.

21021101102221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1530381.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21021101102221 its reverse (12220110112012), we get a palindrome (33241211214233).

The spelling of 21021101102221 in words is "twenty-one trillion, twenty-one billion, one hundred one million, one hundred two thousand, two hundred twenty-one".