21220013321 has 12 divisors (see below), whose sum is σ = 23019991632. Its totient is φ = 19551810096.

The previous prime is 21220013303. The next prime is 21220013323. The reversal of 21220013321 is 12331002212.

It is not a de Polignac number, because 21220013321 - 2¹⁸ = 21219751177 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21220013321.

It is not an unprimeable number, because it can be changed into a prime (21220013323) 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, 22331 + ... + 207216.

It is an arithmetic number, because the mean of its divisors is an integer number (1918332636).

Almost surely, 2^21220013321 is an apocalyptic number.

It is an amenable number.

21220013321 is a deficient number, since it is larger than the sum of its proper divisors (1799978311).

21220013321 is a wasteful number, since it uses less digits than its factorization.

21220013321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230120 (or 230107 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21220013321 its reverse (12331002212), we get a palindrome (33551015533).

The spelling of 21220013321 in words is "twenty-one billion, two hundred twenty million, thirteen thousand, three hundred twenty-one".