21311424424 has 16 divisors (see below), whose sum is σ = 41247918720. Its totient is φ = 10311979440.

The previous prime is 21311424389. The next prime is 21311424439. The reversal of 21311424424 is 42442411312.

It is a junction number, because it is equal to n+sod(n) for n = 21311424392 and 21311424401.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42966334 + ... + 42966829.

It is an arithmetic number, because the mean of its divisors is an integer number (2577994920).

Almost surely, 2^21311424424 is an apocalyptic number.

It is an amenable number.

21311424424 is a deficient number, since it is larger than the sum of its proper divisors (19936494296).

21311424424 is a wasteful number, since it uses less digits than its factorization.

21311424424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85933200 (or 85933196 counting only the distinct ones).

The product of its digits is 6144, while the sum is 28.

Adding to 21311424424 its reverse (42442411312), we get a palindrome (63753835736).

The spelling of 21311424424 in words is "twenty-one billion, three hundred eleven million, four hundred twenty-four thousand, four hundred twenty-four".