21244304424 has 64 divisors (see below), whose sum is σ = 60709017600. Its totient is φ = 6068700864.

The previous prime is 21244304387. The next prime is 21244304429. The reversal of 21244304424 is 42440344212.

It is a junction number, because it is equal to n+sod(n) for n = 21244304391 and 21244304400.

It is not an unprimeable number, because it can be changed into a prime (21244304429) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1545309 + ... + 1558995.

It is an arithmetic number, because the mean of its divisors is an integer number (948578400).

Almost surely, 2^21244304424 is an apocalyptic number.

21244304424 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21244304424 is an abundant number, since it is smaller than the sum of its proper divisors (39464713176).

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

21244304424 is a wasteful number, since it uses less digits than its factorization.

21244304424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22942 (or 22938 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 30.

Adding to 21244304424 its reverse (42440344212), we get a palindrome (63684648636).

The spelling of 21244304424 in words is "twenty-one billion, two hundred forty-four million, three hundred four thousand, four hundred twenty-four".