21100100102221 has 4 divisors (see below), whose sum is σ = 24114400116832. Its totient is φ = 18085800087612.

The previous prime is 21100100102171. The next prime is 21100100102227. The reversal of 21100100102221 is 12220100100112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21100100102221 - 2¹⁹ = 21100099577933 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100100102227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1507150007295 + ... + 1507150007308.

It is an arithmetic number, because the mean of its divisors is an integer number (6028600029208).

Almost surely, 2^{21100100102221} is an apocalyptic number.

It is an amenable number.

21100100102221 is a deficient number, since it is larger than the sum of its proper divisors (3014300014611).

21100100102221 is an equidigital number, since it uses as much as digits as its factorization.

21100100102221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3014300014610.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21100100102221 its reverse (12220100100112), we get a palindrome (33320200202333).

The spelling of 21100100102221 in words is "twenty-one trillion, one hundred billion, one hundred million, one hundred two thousand, two hundred twenty-one".