2161585660 has 24 divisors (see below), whose sum is σ = 4888509696. Its totient is φ = 798123840.

The previous prime is 2161585637. The next prime is 2161585663. The reversal of 2161585660 is 665851612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161585663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4156636 + ... + 4157155.

It is an arithmetic number, because the mean of its divisors is an integer number (203687904).

Almost surely, 2^2161585660 is an apocalyptic number.

2161585660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2161585660 is an abundant number, since it is smaller than the sum of its proper divisors (2726924036).

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

2161585660 is a wasteful number, since it uses less digits than its factorization.

2161585660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8313813 (or 8313811 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 40.

The square root of 2161585660 is about 46492.8560103593. The cubic root of 2161585660 is about 1292.9770515474.

The spelling of 2161585660 in words is "two billion, one hundred sixty-one million, five hundred eighty-five thousand, six hundred sixty".