21002102311221 has 24 divisors (see below), whose sum is σ = 32273093983104. Its totient is φ = 13115335685760.

The previous prime is 21002102311217. The next prime is 21002102311237. The reversal of 21002102311221 is 12211320120012.

21002102311221 is a `hidden beast` number, since 2 + 1 + 0 + 0 + 210 + 231 + 1 + 221 = 666.

It is not a de Polignac number, because 21002102311221 - 2² = 21002102311217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21002102311194 and 21002102311203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002102311271) 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 23 ways as a sum of consecutive naturals, for example, 325248861 + ... + 325313426.

It is an arithmetic number, because the mean of its divisors is an integer number (1344712249296).

Almost surely, 2^{21002102311221} is an apocalyptic number.

It is an amenable number.

21002102311221 is a deficient number, since it is larger than the sum of its proper divisors (11270991671883).

21002102311221 is a wasteful number, since it uses less digits than its factorization.

21002102311221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 650562521 (or 650562518 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 21002102311221 its reverse (12211320120012), we get a palindrome (33213422431233).

The spelling of 21002102311221 in words is "twenty-one trillion, two billion, one hundred two million, three hundred eleven thousand, two hundred twenty-one".