2161201968 has 180 divisors, whose sum is σ = 6554762760. Its totient is φ = 662888448.

The previous prime is 2161201967. The next prime is 2161201997. The reversal of 2161201968 is 8691021612.

2161201968 is a `hidden beast` number, since 21 + 612 + 0 + 19 + 6 + 8 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (2161201961) 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 35 ways as a sum of consecutive naturals, for example, 3745296 + ... + 3745872.

Almost surely, 2^2161201968 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 2161201968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3277381380).

2161201968 is an abundant number, since it is smaller than the sum of its proper divisors (4393560792).

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

2161201968 is a wasteful number, since it uses less digits than its factorization.

2161201968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 684 (or 638 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 2161201968 is about 46488.7294728518. The cubic root of 2161201968 is about 1292.9005437755.

The spelling of 2161201968 in words is "two billion, one hundred sixty-one million, two hundred one thousand, nine hundred sixty-eight".