165899606505 has 8 divisors (see below), whose sum is σ = 265439370432. Its totient is φ = 88479790128.

The previous prime is 165899606459. The next prime is 165899606527. The reversal of 165899606505 is 505606998561.

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

It is not a de Polignac number, because 165899606505 - 2¹¹ = 165899604457 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5529986869 + ... + 5529986898.

It is an arithmetic number, because the mean of its divisors is an integer number (33179921304).

Almost surely, 2^165899606505 is an apocalyptic number.

165899606505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

165899606505 is a deficient number, since it is larger than the sum of its proper divisors (99539763927).

165899606505 is a wasteful number, since it uses less digits than its factorization.

165899606505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11059973775.

The product of its (nonzero) digits is 17496000, while the sum is 60.

The spelling of 165899606505 in words is "one hundred sixty-five billion, eight hundred ninety-nine million, six hundred six thousand, five hundred five".