2155206853800 has 576 divisors, whose sum is σ = 9718031756160. Its totient is φ = 413385984000.

The previous prime is 2155206853783. The next prime is 2155206853831. The reversal of 2155206853800 is 83586025512.

2155206853800 is a `hidden beast` number, since 2 + 1 + 5 + 52 + 0 + 68 + 538 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 1203730 + ... + 2399870.

It is an arithmetic number, because the mean of its divisors is an integer number (16871582910).

Almost surely, 2^{2155206853800} is an apocalyptic number.

2155206853800 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 2155206853800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4859015878080).

2155206853800 is an abundant number, since it is smaller than the sum of its proper divisors (7562824902360).

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

2155206853800 is a wasteful number, since it uses less digits than its factorization.

2155206853800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1196194 (or 1196182 counting only the distinct ones).

The product of its (nonzero) digits is 576000, while the sum is 45.

The spelling of 2155206853800 in words is "two trillion, one hundred fifty-five billion, two hundred six million, eight hundred fifty-three thousand, eight hundred".