171665145 has 48 divisors (see below), whose sum is σ = 305690112. Its totient is φ = 89082240.

The previous prime is 171665141. The next prime is 171665147. The reversal of 171665145 is 541566171.

It is a happy number.

It is not a de Polignac number, because 171665145 - 2² = 171665141 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (171665141) 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 47 ways as a sum of consecutive naturals, for example, 398080 + ... + 398510.

It is an arithmetic number, because the mean of its divisors is an integer number (6368544).

Almost surely, 2^171665145 is an apocalyptic number.

171665145 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

171665145 is a deficient number, since it is larger than the sum of its proper divisors (134024967).

171665145 is a wasteful number, since it uses less digits than its factorization.

171665145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 662 (or 659 counting only the distinct ones).

The product of its digits is 25200, while the sum is 36.

The square root of 171665145 is about 13102.1046019332. The cubic root of 171665145 is about 555.7686452269.

The spelling of 171665145 in words is "one hundred seventy-one million, six hundred sixty-five thousand, one hundred forty-five".