21212323321 has 8 divisors (see below), whose sum is σ = 25296683904. Its totient is φ = 17391469920.

The previous prime is 21212323271. The next prime is 21212323333. The reversal of 21212323321 is 12332321212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21212323321 - 2⁷ = 21212323193 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21212323292 and 21212323301.

It is not an unprimeable number, because it can be changed into a prime (21212323621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 65876620 + ... + 65876941.

It is an arithmetic number, because the mean of its divisors is an integer number (3162085488).

Almost surely, 2^21212323321 is an apocalyptic number.

It is an amenable number.

21212323321 is a deficient number, since it is larger than the sum of its proper divisors (4084360583).

21212323321 is a wasteful number, since it uses less digits than its factorization.

21212323321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131753591.

The product of its digits is 864, while the sum is 22.

Adding to 21212323321 its reverse (12332321212), we get a palindrome (33544644533).

The spelling of 21212323321 in words is "twenty-one billion, two hundred twelve million, three hundred twenty-three thousand, three hundred twenty-one".