18161786165 has 16 divisors (see below), whose sum is σ = 22061258496. Its totient is φ = 14352024000.

The previous prime is 18161786161. The next prime is 18161786191. The reversal of 18161786165 is 56168716181.

It is not a de Polignac number, because 18161786165 - 2² = 18161786161 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18161786161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 175934 + ... + 259376.

It is an arithmetic number, because the mean of its divisors is an integer number (1378828656).

Almost surely, 2^18161786165 is an apocalyptic number.

It is an amenable number.

18161786165 is a deficient number, since it is larger than the sum of its proper divisors (3899472331).

18161786165 is a wasteful number, since it uses less digits than its factorization.

18161786165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83980.

The product of its digits is 483840, while the sum is 50.

The spelling of 18161786165 in words is "eighteen billion, one hundred sixty-one million, seven hundred eighty-six thousand, one hundred sixty-five".