21202313121 has 12 divisors (see below), whose sum is σ = 33409705680. Its totient is φ = 12849886680.

The previous prime is 21202313089. The next prime is 21202313141. The reversal of 21202313121 is 12131320212.

21202313121 is a `hidden beast` number, since 2 + 120 + 231 + 312 + 1 = 666.

It is not a de Polignac number, because 21202313121 - 2⁵ = 21202313089 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21202313094 and 21202313103.

It is not an unprimeable number, because it can be changed into a prime (21202313141) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 107082291 + ... + 107082488.

It is an arithmetic number, because the mean of its divisors is an integer number (2784142140).

Almost surely, 2^21202313121 is an apocalyptic number.

It is an amenable number.

21202313121 is a deficient number, since it is larger than the sum of its proper divisors (12207392559).

21202313121 is a wasteful number, since it uses less digits than its factorization.

21202313121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214164796 (or 214164793 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21202313121 its reverse (12131320212), we get a palindrome (33333633333).

The spelling of 21202313121 in words is "twenty-one billion, two hundred two million, three hundred thirteen thousand, one hundred twenty-one".