21002310013 has 4 divisors (see below), whose sum is σ = 21006178300. Its totient is φ = 20998441728.

The previous prime is 21002310011. The next prime is 21002310031. The reversal of 21002310013 is 31001320012.

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 5987973924 + 15014336089 = 77382^2 + 122533^2 .

It is a cyclic number.

It is not a de Polignac number, because 21002310013 - 2¹ = 21002310011 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21002309975 and 21002310002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002310011) 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, 1925988 + ... + 1936861.

It is an arithmetic number, because the mean of its divisors is an integer number (5251544575).

Almost surely, 2^21002310013 is an apocalyptic number.

It is an amenable number.

21002310013 is a deficient number, since it is larger than the sum of its proper divisors (3868287).

21002310013 is an equidigital number, since it uses as much as digits as its factorization.

21002310013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3868286.

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 21002310013 its reverse (31001320012), we get a palindrome (52003630025).

Subtracting 21002310013 from its reverse (31001320012), we obtain a palindrome (9999009999).

The spelling of 21002310013 in words is "twenty-one billion, two million, three hundred ten thousand, thirteen".