2117789856 has 288 divisors, whose sum is σ = 7804218240. Its totient is φ = 529016832.

The previous prime is 2117789833. The next prime is 2117789881. The reversal of 2117789856 is 6589877112.

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

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, 495826 + ... + 500078.

It is an arithmetic number, because the mean of its divisors is an integer number (27097980).

Almost surely, 2^2117789856 is an apocalyptic number.

2117789856 is a gapful number since it is divisible by the number (26) 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 2117789856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3902109120).

2117789856 is an abundant number, since it is smaller than the sum of its proper divisors (5686428384).

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

2117789856 is a wasteful number, since it uses less digits than its factorization.

2117789856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4308 (or 4297 counting only the distinct ones).

The product of its digits is 1693440, while the sum is 54.

The square root of 2117789856 is about 46019.4508441811. The cubic root of 2117789856 is about 1284.1850841006.

The spelling of 2117789856 in words is "two billion, one hundred seventeen million, seven hundred eighty-nine thousand, eight hundred fifty-six".