2181791128 has 64 divisors (see below), whose sum is σ = 4706352000. Its totient is φ = 937785600.

The previous prime is 2181791119. The next prime is 2181791153. The reversal of 2181791128 is 8211971812.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1355188 + ... + 1356796.

It is an arithmetic number, because the mean of its divisors is an integer number (73536750).

Almost surely, 2^2181791128 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2181791128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2353176000).

2181791128 is an abundant number, since it is smaller than the sum of its proper divisors (2524560872).

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

2181791128 is a wasteful number, since it uses less digits than its factorization.

2181791128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2456 (or 2452 counting only the distinct ones).

The product of its digits is 16128, while the sum is 40.

The square root of 2181791128 is about 46709.6470549714. The cubic root of 2181791128 is about 1296.9932736903.

The spelling of 2181791128 in words is "two billion, one hundred eighty-one million, seven hundred ninety-one thousand, one hundred twenty-eight".