21002100200221 has 16 divisors (see below), whose sum is σ = 24080431085568. Its totient is φ = 17943281132400.

The previous prime is 21002100200219. The next prime is 21002100200233. The reversal of 21002100200221 is 12200200120012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21002100200221 - 2¹ = 21002100200219 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 (21002100200201) 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, 67468866 + ... + 67779436.

It is an arithmetic number, because the mean of its divisors is an integer number (1505026942848).

Almost surely, 2^{21002100200221} is an apocalyptic number.

It is an amenable number.

21002100200221 is a deficient number, since it is larger than the sum of its proper divisors (3078330885347).

21002100200221 is a wasteful number, since it uses less digits than its factorization.

21002100200221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341952.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21002100200221 its reverse (12200200120012), we get a palindrome (33202300320233).

The spelling of 21002100200221 in words is "twenty-one trillion, two billion, one hundred million, two hundred thousand, two hundred twenty-one".