2155591680 has 192 divisors, whose sum is σ = 7524316800. Its totient is φ = 522485760.

The previous prime is 2155591657. The next prime is 2155591699. The reversal of 2155591680 is 861955512.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (192).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 334731 + ... + 341109.

It is an arithmetic number, because the mean of its divisors is an integer number (39189150).

Almost surely, 2^2155591680 is an apocalyptic number.

2155591680 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 2155591680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3762158400).

2155591680 is an abundant number, since it is smaller than the sum of its proper divisors (5368725120).

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

2155591680 is a wasteful number, since it uses less digits than its factorization.

2155591680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6420 (or 6400 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 42.

The square root of 2155591680 is about 46428.3499599113. The cubic root of 2155591680 is about 1291.7808227284.

The spelling of 2155591680 in words is "two billion, one hundred fifty-five million, five hundred ninety-one thousand, six hundred eighty".