2181181800 has 192 divisors, whose sum is σ = 7770931200. Its totient is φ = 495763200.

The previous prime is 2181181799. The next prime is 2181181813. The reversal of 2181181800 is 81811812.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 800841 + ... + 803559.

It is an arithmetic number, because the mean of its divisors is an integer number (40473600).

Almost surely, 2^2181181800 is an apocalyptic number.

2181181800 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 2181181800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3885465600).

2181181800 is an abundant number, since it is smaller than the sum of its proper divisors (5589749400).

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

2181181800 is a wasteful number, since it uses less digits than its factorization.

2181181800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2936 (or 2927 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 30.

The square root of 2181181800 is about 46703.1240925058. The cubic root of 2181181800 is about 1296.8725215417.

The spelling of 2181181800 in words is "two billion, one hundred eighty-one million, one hundred eighty-one thousand, eight hundred".