21443021400 has 96 divisors (see below), whose sum is σ = 70383597840. Its totient is φ = 5381775360.

The previous prime is 21443021381. The next prime is 21443021407. The reversal of 21443021400 is 412034412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21443021407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1040929 + ... + 1061328.

Almost surely, 2^21443021400 is an apocalyptic number.

21443021400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21443021400 is an abundant number, since it is smaller than the sum of its proper divisors (48940576440).

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

21443021400 is a wasteful number, since it uses less digits than its factorization.

21443021400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2102293 (or 2102284 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

Adding to 21443021400 its reverse (412034412), we get a palindrome (21855055812).

The spelling of 21443021400 in words is "twenty-one billion, four hundred forty-three million, twenty-one thousand, four hundred".