171945 has 12 divisors (see below), whose sum is σ = 298116. Its totient is φ = 91680.

The previous prime is 171937. The next prime is 171947. The reversal of 171945 is 549171.

It can be written as a sum of positive squares in 2 ways, for example, as 112896 + 59049 = 336^2 + 243^2 .

It is not a de Polignac number, because 171945 - 2³ = 171937 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (171947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1866 + ... + 1955.

It is an arithmetic number, because the mean of its divisors is an integer number (24843).

2¹⁷¹⁹⁴⁵ is an apocalyptic number.

171945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

171945 is a deficient number, since it is larger than the sum of its proper divisors (126171).

171945 is a wasteful number, since it uses less digits than its factorization.

171945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3832 (or 3829 counting only the distinct ones).

The product of its digits is 1260, while the sum is 27.

The square root of 171945 is about 414.6625133768. The cubic root of 171945 is about 55.6070492934.

It can be divided in two parts, 1719 and 45, that added together give a square (1764 = 42²).

The spelling of 171945 in words is "one hundred seventy-one thousand, nine hundred forty-five".