21865603200 has 1152 divisors, whose sum is σ = 91357009920. Its totient is φ = 4570030080.

The previous prime is 21865603187. The next prime is 21865603211. The reversal of 21865603200 is 230656812.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 465225577 + ... + 465225623.

It is an arithmetic number, because the mean of its divisors is an integer number (79302960).

Almost surely, 2^21865603200 is an apocalyptic number.

21865603200 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 21865603200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45678504960).

21865603200 is an abundant number, since it is smaller than the sum of its proper divisors (69491406720).

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

21865603200 is a wasteful number, since it uses less digits than its factorization.

21865603200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154 (or 130 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The spelling of 21865603200 in words is "twenty-one billion, eight hundred sixty-five million, six hundred three thousand, two hundred".