165131091 has 6 divisors (see below), whose sum is σ = 238522700. Its totient is φ = 110087388.

The previous prime is 165131089. The next prime is 165131101. The reversal of 165131091 is 190131561.

165131091 is a `hidden beast` number, since 1 + 651 + 3 + 1 + 0 + 9 + 1 = 666.

It is not a de Polignac number, because 165131091 - 2¹ = 165131089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165131041) 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 5 ways as a sum of consecutive naturals, for example, 9173941 + ... + 9173958.

Almost surely, 2^165131091 is an apocalyptic number.

165131091 is a deficient number, since it is larger than the sum of its proper divisors (73391609).

165131091 is a wasteful number, since it uses less digits than its factorization.

165131091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18347905 (or 18347902 counting only the distinct ones).

The product of its (nonzero) digits is 810, while the sum is 27.

The square root of 165131091 is about 12850.3342758078. The cubic root of 165131091 is about 548.6258710906.

The spelling of 165131091 in words is "one hundred sixty-five million, one hundred thirty-one thousand, ninety-one".