20865801600 has 1152 divisors, whose sum is σ = 91156665600. Its totient is φ = 4443586560.

The previous prime is 20865801599. The next prime is 20865801611. The reversal of 20865801600 is 610856802.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (1152).

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 251395159 + ... + 251395241.

It is an arithmetic number, because the mean of its divisors is an integer number (79129050).

Almost surely, 2^20865801600 is an apocalyptic number.

20865801600 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 20865801600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45578332800).

20865801600 is an abundant number, since it is smaller than the sum of its proper divisors (70290864000).

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

20865801600 is a wasteful number, since it uses less digits than its factorization.

20865801600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192 (or 172 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The spelling of 20865801600 in words is "twenty billion, eight hundred sixty-five million, eight hundred one thousand, six hundred".