2165981671365 has 32 divisors (see below), whose sum is σ = 3716798762880. Its totient is φ = 1073741849856.

The previous prime is 2165981671361. The next prime is 2165981671391. The reversal of 2165981671365 is 5631761895612.

It is a happy number.

It is not a de Polignac number, because 2165981671365 - 2² = 2165981671361 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2165981671299 and 2165981671308.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2165981671361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 71682402 + ... + 71712611.

It is an arithmetic number, because the mean of its divisors is an integer number (116149961340).

Almost surely, 2^{2165981671365} is an apocalyptic number.

It is an amenable number.

2165981671365 is a deficient number, since it is larger than the sum of its proper divisors (1550817091515).

2165981671365 is a wasteful number, since it uses less digits than its factorization.

2165981671365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143395093.

The product of its digits is 16329600, while the sum is 60.

The spelling of 2165981671365 in words is "two trillion, one hundred sixty-five billion, nine hundred eighty-one million, six hundred seventy-one thousand, three hundred sixty-five".