165915855 has 24 divisors (see below), whose sum is σ = 328672032. Its totient is φ = 75847104.

The previous prime is 165915851. The next prime is 165915857. The reversal of 165915855 is 558519561.

165915855 is a `hidden beast` number, since 1 + 6 + 591 + 5 + 8 + 55 = 666.

It is not a de Polignac number, because 165915855 - 2² = 165915851 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 165915855.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165915851) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 263044 + ... + 263673.

It is an arithmetic number, because the mean of its divisors is an integer number (13694668).

Almost surely, 2^165915855 is an apocalyptic number.

165915855 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

165915855 is a deficient number, since it is larger than the sum of its proper divisors (162756177).

165915855 is a wasteful number, since it uses less digits than its factorization.

165915855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 526735 (or 526732 counting only the distinct ones).

The product of its digits is 270000, while the sum is 45.

The square root of 165915855 is about 12880.8328535076. The cubic root of 165915855 is about 549.4935889629.

The spelling of 165915855 in words is "one hundred sixty-five million, nine hundred fifteen thousand, eight hundred fifty-five".