21321031013 has 24 divisors (see below), whose sum is σ = 22911686400. Its totient is φ = 19785620736.

The previous prime is 21321030989. The next prime is 21321031019. The reversal of 21321031013 is 31013012312.

It is not a de Polignac number, because 21321031013 - 2¹² = 21321026917 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21321030982 and 21321031000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21321031019) 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, 31680245 + ... + 31680917.

It is an arithmetic number, because the mean of its divisors is an integer number (954653600).

Almost surely, 2^21321031013 is an apocalyptic number.

It is an amenable number.

21321031013 is a deficient number, since it is larger than the sum of its proper divisors (1590655387).

21321031013 is an equidigital number, since it uses as much as digits as its factorization.

21321031013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1289 (or 1230 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 17.

Adding to 21321031013 its reverse (31013012312), we get a palindrome (52334043325).

The spelling of 21321031013 in words is "twenty-one billion, three hundred twenty-one million, thirty-one thousand, thirteen".