180545 has 4 divisors (see below), whose sum is σ = 216660. Its totient is φ = 144432.

The previous prime is 180541. The next prime is 180547. The reversal of 180545 is 545081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 545081 = 397 ⋅1373.

It can be written as a sum of positive squares in 2 ways, for example, as 142129 + 38416 = 377^2 + 196^2 .

It is a cyclic number.

It is not a de Polignac number, because 180545 - 2² = 180541 is a prime.

It is an Ulam number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 180545.

It is not an unprimeable number, because it can be changed into a prime (180541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18050 + ... + 18059.

It is an arithmetic number, because the mean of its divisors is an integer number (54165).

2¹⁸⁰⁵⁴⁵ is an apocalyptic number.

It is an amenable number.

180545 is a deficient number, since it is larger than the sum of its proper divisors (36115).

180545 is an equidigital number, since it uses as much as digits as its factorization.

180545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36114.

The product of its (nonzero) digits is 800, while the sum is 23.

The square root of 180545 is about 424.9058719293. The cubic root of 180545 is about 56.5190892763.

It can be divided in two parts, 1805 and 45, that multiplied together give a square (81225 = 285²).

The spelling of 180545 in words is "one hundred eighty thousand, five hundred forty-five".