2181816000 has 1120 divisors, whose sum is σ = 10202704512. Its totient is φ = 447897600.

The previous prime is 2181815981. The next prime is 2181816017. The reversal of 2181816000 is 6181812.

It is a tau number, because it is divible by the number of its divisors (1120).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 58967982 + ... + 58968018.

Almost surely, 2^2181816000 is an apocalyptic number.

2181816000 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 2181816000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5101352256).

2181816000 is an abundant number, since it is smaller than the sum of its proper divisors (8020888512).

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

2181816000 is a wasteful number, since it uses less digits than its factorization.

2181816000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96 (or 67 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 27.

The square root of 2181816000 is about 46709.9132947172. The cubic root of 2181816000 is about 1296.9982021630.

Adding to 2181816000 its reverse (6181812), we get a palindrome (2187997812).

The spelling of 2181816000 in words is "two billion, one hundred eighty-one million, eight hundred sixteen thousand".