21443121200 has 30 divisors (see below), whose sum is σ = 51517099644. Its totient is φ = 8577248320.

The previous prime is 21443121199. The next prime is 21443121209. The reversal of 21443121200 is 212134412.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (21443121209) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 26803502 + ... + 26804301.

Almost surely, 2^21443121200 is an apocalyptic number.

21443121200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21443121200 is an abundant number, since it is smaller than the sum of its proper divisors (30073978444).

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

21443121200 is a wasteful number, since it uses less digits than its factorization.

21443121200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53607821 (or 53607810 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21443121200 its reverse (212134412), we get a palindrome (21655255612).

The spelling of 21443121200 in words is "twenty-one billion, four hundred forty-three million, one hundred twenty-one thousand, two hundred".