21042243200 has 192 divisors, whose sum is σ = 56854530720. Its totient is φ = 7631769600.

The previous prime is 21042243137. The next prime is 21042243217. The reversal of 21042243200 is 234224012.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23829959 + ... + 23830841.

Almost surely, 2^21042243200 is an apocalyptic number.

21042243200 is a gapful number since it is divisible by the number (20) 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 21042243200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28427265360).

21042243200 is an abundant number, since it is smaller than the sum of its proper divisors (35812287520).

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

21042243200 is a wasteful number, since it uses less digits than its factorization.

21042243200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1595 (or 1578 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

Adding to 21042243200 its reverse (234224012), we get a palindrome (21276467212).

The spelling of 21042243200 in words is "twenty-one billion, forty-two million, two hundred forty-three thousand, two hundred".