21224001024 has 280 divisors, whose sum is σ = 64324300392. Its totient is φ = 6992179200.

The previous prime is 21224000953. The next prime is 21224001041. The reversal of 21224001024 is 42010042212.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21224000988 and 21224001006.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 37697767 + ... + 37698329.

Almost surely, 2^21224001024 is an apocalyptic number.

21224001024 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21224001024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32162150196).

21224001024 is an abundant number, since it is smaller than the sum of its proper divisors (43100299368).

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

21224001024 is an frugal number, since it uses more digits than its factorization.

21224001024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 700 (or 669 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 21224001024 its reverse (42010042212), we get a palindrome (63234043236).

The spelling of 21224001024 in words is "twenty-one billion, two hundred twenty-four million, one thousand, twenty-four".