2161323648 has 192 divisors, whose sum is σ = 7037241120. Its totient is φ = 654842880.

The previous prime is 2161323643. The next prime is 2161323667. The reversal of 2161323648 is 8463231612.

2161323648 is a `hidden beast` number, since 2 + 1 + 6 + 1 + 3 + 2 + 3 + 648 = 666.

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

It is a super-2 number, since 2×2161323648² = 9342639822808055808, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (2161323643) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 338986 + ... + 345302.

Almost surely, 2^2161323648 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 2161323648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3518620560).

2161323648 is an abundant number, since it is smaller than the sum of its proper divisors (4875917472).

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

2161323648 is an equidigital number, since it uses as much as digits as its factorization.

2161323648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6357 (or 6333 counting only the distinct ones).

The product of its digits is 41472, while the sum is 36.

The square root of 2161323648 is about 46490.0381587282. The cubic root of 2161323648 is about 1292.9248076170.

The spelling of 2161323648 in words is "two billion, one hundred sixty-one million, three hundred twenty-three thousand, six hundred forty-eight".