169945 has 8 divisors (see below), whose sum is σ = 209160. Its totient is φ = 132480.

The previous prime is 169943. The next prime is 169951. The reversal of 169945 is 549961.

169945 = 291² + 292².

It can be written as a sum of positive squares in 4 ways, for example, as 1024 + 168921 = 32^2 + 411^2 .

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

It is not a de Polignac number, because 169945 - 2¹ = 169943 is a prime.

169945 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 169945.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (169943) 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 7 ways as a sum of consecutive naturals, for example, 210 + ... + 619.

It is an arithmetic number, because the mean of its divisors is an integer number (26145).

2¹⁶⁹⁹⁴⁵ is an apocalyptic number.

169945 is the 292-nd centered square number.

It is an amenable number.

169945 is a deficient number, since it is larger than the sum of its proper divisors (39215).

169945 is an equidigital number, since it uses as much as digits as its factorization.

169945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 875.

The product of its digits is 9720, while the sum is 34.

The square root of 169945 is about 412.2438598694. The cubic root of 169945 is about 55.3906077819.

The spelling of 169945 in words is "one hundred sixty-nine thousand, nine hundred forty-five".