21230320013 has 12 divisors (see below), whose sum is σ = 25101358812. Its totient is φ = 17899096320.

The previous prime is 21230319991. The next prime is 21230320037. The reversal of 21230320013 is 31002303212.

It can be written as a sum of positive squares in 2 ways, for example, as 8197129444 + 13033190569 = 90538^2 + 114163^2 .

It is not a de Polignac number, because 21230320013 - 2¹⁶ = 21230254477 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21230319973 and 21230320000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21230320093) 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, 3548420 + ... + 3554397.

It is an arithmetic number, because the mean of its divisors is an integer number (2091779901).

Almost surely, 2^21230320013 is an apocalyptic number.

It is an amenable number.

21230320013 is a deficient number, since it is larger than the sum of its proper divisors (3871038799).

21230320013 is an equidigital number, since it uses as much as digits as its factorization.

21230320013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7102892 (or 7102885 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 17.

Adding to 21230320013 its reverse (31002303212), we get a palindrome (52232623225).

The spelling of 21230320013 in words is "twenty-one billion, two hundred thirty million, three hundred twenty thousand, thirteen".