21331311311305 has 32 divisors (see below), whose sum is σ = 25765186857984. Its totient is φ = 16953658235136.

The previous prime is 21331311311293. The next prime is 21331311311311. The reversal of 21331311311305 is 50311311313312.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21331311311305 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1137235987 + ... + 1137254743.

It is an arithmetic number, because the mean of its divisors is an integer number (805162089312).

Almost surely, 2^{21331311311305} is an apocalyptic number.

It is an amenable number.

21331311311305 is a deficient number, since it is larger than the sum of its proper divisors (4433875546679).

21331311311305 is a wasteful number, since it uses less digits than its factorization.

21331311311305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21025.

The product of its (nonzero) digits is 2430, while the sum is 28.

Adding to 21331311311305 its reverse (50311311313312), we get a palindrome (71642622624617).

The spelling of 21331311311305 in words is "twenty-one trillion, three hundred thirty-one billion, three hundred eleven million, three hundred eleven thousand, three hundred five".