209045 has 4 divisors (see below), whose sum is σ = 250860. Its totient is φ = 167232.

The previous prime is 209039. The next prime is 209063. The reversal of 209045 is 540902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 540902 = 2 ⋅270451.

It can be written as a sum of positive squares in 2 ways, for example, as 69169 + 139876 = 263^2 + 374^2 .

It is a cyclic number.

It is not a de Polignac number, because 209045 - 2⁴ = 209029 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20900 + ... + 20909.

It is an arithmetic number, because the mean of its divisors is an integer number (62715).

2²⁰⁹⁰⁴⁵ is an apocalyptic number.

It is an amenable number.

209045 is a deficient number, since it is larger than the sum of its proper divisors (41815).

209045 is an equidigital number, since it uses as much as digits as its factorization.

209045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41814.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 209045 is about 457.2143917245. The cubic root of 209045 is about 59.3489802889.

Adding to 209045 its reverse (540902), we get a palindrome (749947).

The spelling of 209045 in words is "two hundred nine thousand, forty-five".