21240235200 has 336 divisors, whose sum is σ = 74385489024. Its totient is φ = 5287526400.

The previous prime is 21240235199. The next prime is 21240235231. The reversal of 21240235200 is 253204212.

It is a super-2 number, since 2×21240235200² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 10688607 + ... + 10690593.

It is an arithmetic number, because the mean of its divisors is an integer number (221385384).

Almost surely, 2^21240235200 is an apocalyptic number.

21240235200 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 21240235200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37192744512).

21240235200 is an abundant number, since it is smaller than the sum of its proper divisors (53145253824).

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

21240235200 is a wasteful number, since it uses less digits than its factorization.

21240235200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2160 (or 2145 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 21.

Adding to 21240235200 its reverse (253204212), we get a palindrome (21493439412).

The spelling of 21240235200 in words is "twenty-one billion, two hundred forty million, two hundred thirty-five thousand, two hundred".