2165355999 has 12 divisors (see below), whose sum is σ = 3263725296. Its totient is φ = 1380806592.

The previous prime is 2165355967. The next prime is 2165356007. The reversal of 2165355999 is 9995535612.

It is a happy number.

2165355999 is a `hidden beast` number, since 2 + 16 + 5 + 35 + 599 + 9 = 666.

It is not a de Polignac number, because 2165355999 - 2⁵ = 2165355967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2165355949) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5230122 + ... + 5230535.

It is an arithmetic number, because the mean of its divisors is an integer number (271977108).

Almost surely, 2^2165355999 is an apocalyptic number.

2165355999 is a deficient number, since it is larger than the sum of its proper divisors (1098369297).

2165355999 is a wasteful number, since it uses less digits than its factorization.

2165355999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10460686 (or 10460683 counting only the distinct ones).

The product of its digits is 3280500, while the sum is 54.

The square root of 2165355999 is about 46533.3858535998. The cubic root of 2165355999 is about 1293.7283719412.

The spelling of 2165355999 in words is "two billion, one hundred sixty-five million, three hundred fifty-five thousand, nine hundred ninety-nine".