21335434424 has 8 divisors (see below), whose sum is σ = 40003939560. Its totient is φ = 10667717208.

The previous prime is 21335434423. The next prime is 21335434499. The reversal of 21335434424 is 42443453312.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21335434423) 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 as a sum of consecutive naturals, namely, 1333464644 + ... + 1333464659.

It is an arithmetic number, because the mean of its divisors is an integer number (5000492445).

Almost surely, 2^21335434424 is an apocalyptic number.

It is an amenable number.

21335434424 is a deficient number, since it is larger than the sum of its proper divisors (18668505136).

21335434424 is a wasteful number, since it uses less digits than its factorization.

21335434424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2666929309 (or 2666929305 counting only the distinct ones).

The product of its digits is 138240, while the sum is 35.

Adding to 21335434424 its reverse (42443453312), we get a palindrome (63778887736).

The spelling of 21335434424 in words is "twenty-one billion, three hundred thirty-five million, four hundred thirty-four thousand, four hundred twenty-four".