21210303321 has 24 divisors (see below), whose sum is σ = 30972240000. Its totient is φ = 13986323232.

The previous prime is 21210303293. The next prime is 21210303343. The reversal of 21210303321 is 12330301212.

21210303321 is a `hidden beast` number, since 21 + 21 + 0 + 303 + 321 = 666.

It is not a de Polignac number, because 21210303321 - 2⁹ = 21210302809 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21210303294 and 21210303303.

It is not an unprimeable number, because it can be changed into a prime (21210303371) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 287410 + ... + 353588.

It is an arithmetic number, because the mean of its divisors is an integer number (1290510000).

Almost surely, 2^21210303321 is an apocalyptic number.

It is an amenable number.

21210303321 is a deficient number, since it is larger than the sum of its proper divisors (9761936679).

21210303321 is a wasteful number, since it uses less digits than its factorization.

21210303321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66573 (or 66570 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21210303321 its reverse (12330301212), we get a palindrome (33540604533).

The spelling of 21210303321 in words is "twenty-one billion, two hundred ten million, three hundred three thousand, three hundred twenty-one".