8221909 has 4 divisors (see below), whose sum is σ = 8314380. Its totient is φ = 8129440.

The previous prime is 8221903. The next prime is 8221919. The reversal of 8221909 is 9091228.

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 3478225 + 4743684 = 1865^2 + 2178^2 .

It is a cyclic number.

It is not a de Polignac number, because 8221909 - 2¹³ = 8213717 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8221903) 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, 46102 + ... + 46279.

It is an arithmetic number, because the mean of its divisors is an integer number (2078595).

Almost surely, 2^8221909 is an apocalyptic number.

8221909 is a gapful number since it is divisible by the number (89) formed by its first and last digit.

It is an amenable number.

8221909 is a deficient number, since it is larger than the sum of its proper divisors (92471).

8221909 is an equidigital number, since it uses as much as digits as its factorization.

8221909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92470.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 8221909 is about 2867.3871381451. The cubic root of 8221909 is about 201.8324019108.

The spelling of 8221909 in words is "eight million, two hundred twenty-one thousand, nine hundred nine".