21000231311 has 4 divisors (see below), whose sum is σ = 21001069824. Its totient is φ = 20999392800.

The previous prime is 21000231299. The next prime is 21000231313. The reversal of 21000231311 is 11313200012.

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

It is a cyclic number.

It is not a de Polignac number, because 21000231311 - 2¹⁴ = 21000214927 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 (21000231313) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 380495 + ... + 432176.

It is an arithmetic number, because the mean of its divisors is an integer number (5250267456).

Almost surely, 2^21000231311 is an apocalyptic number.

21000231311 is a deficient number, since it is larger than the sum of its proper divisors (838513).

21000231311 is an equidigital number, since it uses as much as digits as its factorization.

21000231311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 838512.

The product of its (nonzero) digits is 36, while the sum is 14.

Adding to 21000231311 its reverse (11313200012), we get a palindrome (32313431323).

The spelling of 21000231311 in words is "twenty-one billion, two hundred thirty-one thousand, three hundred eleven".