209090 has 32 divisors (see below), whose sum is σ = 449280. Its totient is φ = 68544.

The previous prime is 209089. The next prime is 209123. The reversal of 209090 is 90902.

209090 = 263² + 264² + 265².

209090 is a modest number, since divided by 9090 gives 20 as remainder.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1979 + ... + 2081.

It is an arithmetic number, because the mean of its divisors is an integer number (14040).

2²⁰⁹⁰⁹⁰ is an apocalyptic number.

209090 is an abundant number, since it is smaller than the sum of its proper divisors (240190).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

209090 is a wasteful number, since it uses less digits than its factorization.

209090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146.

The product of its (nonzero) digits is 162, while the sum is 20.

The square root of 209090 is about 457.2636001258. The cubic root of 209090 is about 59.3532385626.

Adding to 209090 its reverse (90902), we get a palindrome (299992).

The spelling of 209090 in words is "two hundred nine thousand, ninety".