21243230311 has 4 divisors (see below), whose sum is σ = 22492832112. Its totient is φ = 19993628512.

The previous prime is 21243230303. The next prime is 21243230339. The reversal of 21243230311 is 11303234212.

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 21243230311 - 2³ = 21243230303 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 (21243230381) 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, 624800875 + ... + 624800908.

It is an arithmetic number, because the mean of its divisors is an integer number (5623208028).

Almost surely, 2^21243230311 is an apocalyptic number.

21243230311 is a deficient number, since it is larger than the sum of its proper divisors (1249601801).

21243230311 is a wasteful number, since it uses less digits than its factorization.

21243230311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1249601800.

The product of its (nonzero) digits is 864, while the sum is 22.

Adding to 21243230311 its reverse (11303234212), we get a palindrome (32546464523).

The spelling of 21243230311 in words is "twenty-one billion, two hundred forty-three million, two hundred thirty thousand, three hundred eleven".