423209 has 2 divisors, whose sum is σ = 423210. Its totient is φ = 423208.

The previous prime is 423191. The next prime is 423221. The reversal of 423209 is 902324.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 384400 + 38809 = 620^2 + 197^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-423209 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (423229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 211604 + 211605.

It is an arithmetic number, because the mean of its divisors is an integer number (211605).

2⁴²³²⁰⁹ is an apocalyptic number.

It is an amenable number.

423209 is a deficient number, since it is larger than the sum of its proper divisors (1).

423209 is an equidigital number, since it uses as much as digits as its factorization.

423209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 423209 is about 650.5451560038. The cubic root of 423209 is about 75.0789686753.

The spelling of 423209 in words is "four hundred twenty-three thousand, two hundred nine".