220811209 has 2 divisors, whose sum is σ = 220811210. Its totient is φ = 220811208.

The previous prime is 220811183. The next prime is 220811231. The reversal of 220811209 is 902118022.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 215649225 + 5161984 = 14685^2 + 2272^2 .

It is a cyclic number.

It is not a de Polignac number, because 220811209 - 2⁷ = 220811081 is a prime.

It is not a weakly prime, because it can be changed into another prime (220811009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110405604 + 110405605.

It is an arithmetic number, because the mean of its divisors is an integer number (110405605).

Almost surely, 2^220811209 is an apocalyptic number.

It is an amenable number.

220811209 is a deficient number, since it is larger than the sum of its proper divisors (1).

220811209 is an equidigital number, since it uses as much as digits as its factorization.

220811209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 220811209 is about 14859.7176621900. The cubic root of 220811209 is about 604.4221507153.

The spelling of 220811209 in words is "two hundred twenty million, eight hundred eleven thousand, two hundred nine".