21224335504 has 80 divisors (see below), whose sum is σ = 42950393856. Its totient is φ = 10149148800.

The previous prime is 21224335501. The next prime is 21224335519. The reversal of 21224335504 is 40553342212.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (21224335501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21857739 + ... + 21858709.

Almost surely, 2^21224335504 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21224335504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21475196928).

21224335504 is an abundant number, since it is smaller than the sum of its proper divisors (21726058352).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21224335504 is a wasteful number, since it uses less digits than its factorization.

21224335504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1484 (or 1478 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 31.

Adding to 21224335504 its reverse (40553342212), we get a palindrome (61777677716).

The spelling of 21224335504 in words is "twenty-one billion, two hundred twenty-four million, three hundred thirty-five thousand, five hundred four".