20821600800 has 1728 divisors, whose sum is σ = 103187395584. Its totient is φ = 3956428800.

The previous prime is 20821600753. The next prime is 20821600837. The reversal of 20821600800 is 800612802.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 194594347 + ... + 194594453.

It is an arithmetic number, because the mean of its divisors is an integer number (59714928).

Almost surely, 2^20821600800 is an apocalyptic number.

20821600800 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 20821600800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51593697792).

20821600800 is an abundant number, since it is smaller than the sum of its proper divisors (82365794784).

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

20821600800 is a wasteful number, since it uses less digits than its factorization.

20821600800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173 (or 148 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The spelling of 20821600800 in words is "twenty billion, eight hundred twenty-one million, six hundred thousand, eight hundred".