21101020221021 has 64 divisors (see below), whose sum is σ = 31815277756416. Its totient is φ = 12353222131200.

The previous prime is 21101020221011. The next prime is 21101020221037. The reversal of 21101020221021 is 12012202010112.

It is not a de Polignac number, because 21101020221021 - 2⁷ = 21101020220893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101020221011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 19848430 + ... + 20884496.

It is an arithmetic number, because the mean of its divisors is an integer number (497113714944).

Almost surely, 2^{21101020221021} is an apocalyptic number.

It is an amenable number.

21101020221021 is a deficient number, since it is larger than the sum of its proper divisors (10714257535395).

21101020221021 is a wasteful number, since it uses less digits than its factorization.

21101020221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1036442.

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

Adding to 21101020221021 its reverse (12012202010112), we get a palindrome (33113222231133).

The spelling of 21101020221021 in words is "twenty-one trillion, one hundred one billion, twenty million, two hundred twenty-one thousand, twenty-one".