21110020100221 has 16 divisors (see below), whose sum is σ = 22891769348224. Its totient is φ = 19350970352064.

The previous prime is 21110020100161. The next prime is 21110020100243. The reversal of 21110020100221 is 12200102001112.

It is not a de Polignac number, because 21110020100221 - 2⁹ = 21110020099709 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110020100251) 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, 605416 + ... + 6525838.

It is an arithmetic number, because the mean of its divisors is an integer number (1430735584264).

Almost surely, 2^{21110020100221} is an apocalyptic number.

It is an amenable number.

21110020100221 is a deficient number, since it is larger than the sum of its proper divisors (1781749248003).

21110020100221 is a wasteful number, since it uses less digits than its factorization.

21110020100221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5922340.

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

Adding to 21110020100221 its reverse (12200102001112), we get a palindrome (33310122101333).

The spelling of 21110020100221 in words is "twenty-one trillion, one hundred ten billion, twenty million, one hundred thousand, two hundred twenty-one".