20115100800 has 288 divisors, whose sum is σ = 74898420480. Its totient is φ = 5130639360.

The previous prime is 20115100787. The next prime is 20115100847. The reversal of 20115100800 is 800151102.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 647217 + ... + 677583.

It is an arithmetic number, because the mean of its divisors is an integer number (260063960).

Almost surely, 2^20115100800 is an apocalyptic number.

20115100800 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 20115100800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37449210240).

20115100800 is an abundant number, since it is smaller than the sum of its proper divisors (54783319680).

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

20115100800 is a wasteful number, since it uses less digits than its factorization.

20115100800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30420 (or 30400 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 18.

Adding to 20115100800 its reverse (800151102), we get a palindrome (20915251902).

The spelling of 20115100800 in words is "twenty billion, one hundred fifteen million, one hundred thousand, eight hundred".