21230323013 has 4 divisors (see below), whose sum is σ = 21230643948. Its totient is φ = 21230002080.

The previous prime is 21230322899. The next prime is 21230323019. The reversal of 21230323013 is 31032303212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17130097924 + 4100225089 = 130882^2 + 64033^2 .

It is a cyclic number.

It is not a de Polignac number, because 21230323013 - 2¹² = 21230318917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21230323019) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20606 + ... + 207087.

It is an arithmetic number, because the mean of its divisors is an integer number (5307660987).

Almost surely, 2^21230323013 is an apocalyptic number.

It is an amenable number.

21230323013 is a deficient number, since it is larger than the sum of its proper divisors (320935).

21230323013 is an equidigital number, since it uses as much as digits as its factorization.

21230323013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320934.

The product of its (nonzero) digits is 648, while the sum is 20.

Adding to 21230323013 its reverse (31032303212), we get a palindrome (52262626225).

The spelling of 21230323013 in words is "twenty-one billion, two hundred thirty million, three hundred twenty-three thousand, thirteen".