21312110311 has 4 divisors (see below), whose sum is σ = 21313570824. Its totient is φ = 21310649800.

The previous prime is 21312110291. The next prime is 21312110363. The reversal of 21312110311 is 11301121312.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21312110311 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 (21312110011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 708145 + ... + 737626.

It is an arithmetic number, because the mean of its divisors is an integer number (5328392706).

Almost surely, 2^21312110311 is an apocalyptic number.

21312110311 is a deficient number, since it is larger than the sum of its proper divisors (1460513).

21312110311 is a wasteful number, since it uses less digits than its factorization.

21312110311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1460512.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 21312110311 its reverse (11301121312), we get a palindrome (32613231623).

The spelling of 21312110311 in words is "twenty-one billion, three hundred twelve million, one hundred ten thousand, three hundred eleven".