18131896165 has 8 divisors (see below), whose sum is σ = 21763905048. Its totient is φ = 14501763840.

The previous prime is 18131896109. The next prime is 18131896207. The reversal of 18131896165 is 56169813181.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 294156801 + 17837739364 = 17151^2 + 133558^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18131896165 - 2²³ = 18123507557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 447792 + ... + 486601.

It is an arithmetic number, because the mean of its divisors is an integer number (2720488131).

Almost surely, 2^18131896165 is an apocalyptic number.

It is an amenable number.

18131896165 is a deficient number, since it is larger than the sum of its proper divisors (3632008883).

18131896165 is an equidigital number, since it uses as much as digits as its factorization.

18131896165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 938279.

The product of its digits is 311040, while the sum is 49.

The spelling of 18131896165 in words is "eighteen billion, one hundred thirty-one million, eight hundred ninety-six thousand, one hundred sixty-five".