21800804000 has 96 divisors (see below), whose sum is σ = 53610757200. Its totient is φ = 8712806400.

The previous prime is 21800803957. The next prime is 21800804071. The reversal of 21800804000 is 40800812.

It can be written as a sum of positive squares in 8 ways, for example, as 3105164176 + 18695639824 = 55724^2 + 136732^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8354696 + ... + 8357304.

Almost surely, 2^21800804000 is an apocalyptic number.

21800804000 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 21800804000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26805378600).

21800804000 is an abundant number, since it is smaller than the sum of its proper divisors (31809953200).

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

21800804000 is a wasteful number, since it uses less digits than its factorization.

21800804000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4723 (or 4705 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 23.

The spelling of 21800804000 in words is "twenty-one billion, eight hundred million, eight hundred four thousand".