8423209 has 2 divisors, whose sum is σ = 8423210. Its totient is φ = 8423208.

The previous prime is 8423201. The next prime is 8423231. The reversal of 8423209 is 9023248.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4717584 + 3705625 = 2172^2 + 1925^2 .

It is a cyclic number.

It is not a de Polignac number, because 8423209 - 2³ = 8423201 is a prime.

8423209 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (8423201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4211604 + 4211605.

It is an arithmetic number, because the mean of its divisors is an integer number (4211605).

Almost surely, 2^8423209 is an apocalyptic number.

It is an amenable number.

8423209 is a deficient number, since it is larger than the sum of its proper divisors (1).

8423209 is an equidigital number, since it uses as much as digits as its factorization.

8423209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 8423209 is about 2902.2765202510. The cubic root of 8423209 is about 203.4663177959.

The spelling of 8423209 in words is "eight million, four hundred twenty-three thousand, two hundred nine".