21313220311305 has 96 divisors (see below), whose sum is σ = 40023835461792. Its totient is φ = 10429643980800.

The previous prime is 21313220311247. The next prime is 21313220311333. The reversal of 21313220311305 is 50311302231312.

21313220311305 is a `hidden beast` number, since 2 + 1 + 3 + 1 + 322 + 0 + 31 + 1 + 305 = 666.

It can be written as a sum of positive squares in 16 ways, for example, as 21279916616256 + 33303695049 = 4613016^2 + 182493^2 .

It is not a de Polignac number, because 21313220311305 - 2¹⁷ = 21313220180233 is a prime.

It is a super-2 number, since 2×21313220311305² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 223687375 + ... + 223782635.

It is an arithmetic number, because the mean of its divisors is an integer number (416914952727).

Almost surely, 2^{21313220311305} is an apocalyptic number.

It is an amenable number.

21313220311305 is a deficient number, since it is larger than the sum of its proper divisors (18710615150487).

21313220311305 is a wasteful number, since it uses less digits than its factorization.

21313220311305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97579 (or 97576 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

Adding to 21313220311305 its reverse (50311302231312), we get a palindrome (71624522542617).

The spelling of 21313220311305 in words is "twenty-one trillion, three hundred thirteen billion, two hundred twenty million, three hundred eleven thousand, three hundred five".