220909 has 4 divisors (see below), whose sum is σ = 237916. Its totient is φ = 203904.

The previous prime is 220907. The next prime is 220919. The reversal of 220909 is 909022.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 31684 + 189225 = 178^2 + 435^2 .

It is a cyclic number.

It is not a de Polignac number, because 220909 - 2¹ = 220907 is a prime.

It is a Duffinian number.

220909 is a modest number, since divided by 909 gives 22 as remainder.

220909 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 220909.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8484 + ... + 8509.

It is an arithmetic number, because the mean of its divisors is an integer number (59479).

2²²⁰⁹⁰⁹ is an apocalyptic number.

It is an amenable number.

220909 is a deficient number, since it is larger than the sum of its proper divisors (17007).

220909 is a wasteful number, since it uses less digits than its factorization.

220909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17006.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 220909 is about 470.0095743706. The cubic root of 220909 is about 60.4511364669.

The spelling of 220909 in words is "two hundred twenty thousand, nine hundred nine".