2165668680 has 288 divisors, whose sum is σ = 7873770240. Its totient is φ = 474647040.

The previous prime is 2165668639. The next prime is 2165668717. The reversal of 2165668680 is 868665612.

It is a happy 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 71 ways as a sum of consecutive naturals, for example, 19868466 + ... + 19868574.

It is an arithmetic number, because the mean of its divisors is an integer number (27339480).

Almost surely, 2^2165668680 is an apocalyptic number.

2165668680 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 2165668680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3936885120).

2165668680 is an abundant number, since it is smaller than the sum of its proper divisors (5708101560).

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

2165668680 is a wasteful number, since it uses less digits than its factorization.

2165668680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277 (or 157 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 48.

The square root of 2165668680 is about 46536.7454813935. The cubic root of 2165668680 is about 1293.7906411187.

The spelling of 2165668680 in words is "two billion, one hundred sixty-five million, six hundred sixty-eight thousand, six hundred eighty".