21010320313 has 4 divisors (see below), whose sum is σ = 21069839988. Its totient is φ = 20950800640.

The previous prime is 21010320299. The next prime is 21010320337. The reversal of 21010320313 is 31302301012.

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 14805292329 + 6205027984 = 121677^2 + 78772^2 .

It is a cyclic number.

It is not a de Polignac number, because 21010320313 - 2²⁵ = 20976765881 is a prime.

It is a super-3 number, since 3×21010320313³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21010320613) 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, 29759308 + ... + 29760013.

It is an arithmetic number, because the mean of its divisors is an integer number (5267459997).

Almost surely, 2^21010320313 is an apocalyptic number.

It is an amenable number.

21010320313 is a deficient number, since it is larger than the sum of its proper divisors (59519675).

21010320313 is an equidigital number, since it uses as much as digits as its factorization.

21010320313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59519674.

The product of its (nonzero) digits is 108, while the sum is 16.

Adding to 21010320313 its reverse (31302301012), we get a palindrome (52312621325).

The spelling of 21010320313 in words is "twenty-one billion, ten million, three hundred twenty thousand, three hundred thirteen".