21210110102221 has 8 divisors (see below), whose sum is σ = 21420241509888. Its totient is φ = 20999981250000.

The previous prime is 21210110102219. The next prime is 21210110102239. The reversal of 21210110102221 is 12220101101212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21210110102221 - 2¹ = 21210110102219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21210110102195 and 21210110102204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210110106221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19026916 + ... + 20110786.

It is an arithmetic number, because the mean of its divisors is an integer number (2677530188736).

Almost surely, 2^{21210110102221} is an apocalyptic number.

It is an amenable number.

21210110102221 is a deficient number, since it is larger than the sum of its proper divisors (210131407667).

21210110102221 is a wasteful number, since it uses less digits than its factorization.

21210110102221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1277723.

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

Adding to 21210110102221 its reverse (12220101101212), we get a palindrome (33430211203433).

The spelling of 21210110102221 in words is "twenty-one trillion, two hundred ten billion, one hundred ten million, one hundred two thousand, two hundred twenty-one".