2165818972 has 24 divisors (see below), whose sum is σ = 4039731360. Its totient is φ = 1012454400.

The previous prime is 2165818933. The next prime is 2165818997. The reversal of 2165818972 is 2798185612.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 95197 + ... + 115732.

It is an arithmetic number, because the mean of its divisors is an integer number (168322140).

Almost surely, 2^2165818972 is an apocalyptic number.

It is an amenable number.

2165818972 is a deficient number, since it is larger than the sum of its proper divisors (1873912388).

2165818972 is a wasteful number, since it uses less digits than its factorization.

2165818972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211101 (or 211099 counting only the distinct ones).

The product of its digits is 483840, while the sum is 49.

The square root of 2165818972 is about 46538.3602203601. The cubic root of 2165818972 is about 1293.8205690400.

The spelling of 2165818972 in words is "two billion, one hundred sixty-five million, eight hundred eighteen thousand, nine hundred seventy-two".