21101002210221 has 16 divisors (see below), whose sum is σ = 28895249856000. Its totient is φ = 13687049521728.

The previous prime is 21101002210217. The next prime is 21101002210273. The reversal of 21101002210221 is 12201220010112.

It is not a de Polignac number, because 21101002210221 - 2² = 21101002210217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21101002210221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101002214221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20110980 + ... + 21134178.

It is an arithmetic number, because the mean of its divisors is an integer number (1805953116000).

Almost surely, 2^{21101002210221} is an apocalyptic number.

It is an amenable number.

21101002210221 is a deficient number, since it is larger than the sum of its proper divisors (7794247645779).

21101002210221 is a wasteful number, since it uses less digits than its factorization.

21101002210221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1209028.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21101002210221 its reverse (12201220010112), we get a palindrome (33302222220333).

The spelling of 21101002210221 in words is "twenty-one trillion, one hundred one billion, two million, two hundred ten thousand, two hundred twenty-one".