2161755512 has 64 divisors (see below), whose sum is σ = 4750099200. Its totient is φ = 903006720.

The previous prime is 2161755509. The next prime is 2161755517. The reversal of 2161755512 is 2155571612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161755517) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2120939 + ... + 2121957.

It is an arithmetic number, because the mean of its divisors is an integer number (74220300).

Almost surely, 2^2161755512 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2161755512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2375049600).

2161755512 is an abundant number, since it is smaller than the sum of its proper divisors (2588343688).

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

2161755512 is a wasteful number, since it uses less digits than its factorization.

2161755512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1956 (or 1952 counting only the distinct ones).

The product of its digits is 21000, while the sum is 35.

The square root of 2161755512 is about 46494.6826207041. The cubic root of 2161755512 is about 1293.0109169623.

The spelling of 2161755512 in words is "two billion, one hundred sixty-one million, seven hundred fifty-five thousand, five hundred twelve".