2091881664 has 168 divisors, whose sum is σ = 6183642192. Its totient is φ = 675717120.

The previous prime is 2091881657. The next prime is 2091881681. The reversal of 2091881664 is 4661881902.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6683172 + ... + 6683484.

It is an arithmetic number, because the mean of its divisors is an integer number (36807394).

Almost surely, 2^2091881664 is an apocalyptic number.

2091881664 is a gapful number since it is divisible by the number (24) 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 2091881664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3091821096).

2091881664 is an abundant number, since it is smaller than the sum of its proper divisors (4091760528).

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

2091881664 is a wasteful number, since it uses less digits than its factorization.

2091881664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 655 (or 642 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The square root of 2091881664 is about 45737.0928678245. The cubic root of 2091881664 is about 1278.9268479165.

The spelling of 2091881664 in words is "two billion, ninety-one million, eight hundred eighty-one thousand, six hundred sixty-four".