423509 has 2 divisors, whose sum is σ = 423510. Its totient is φ = 423508.

The previous prime is 423503. The next prime is 423541. The reversal of 423509 is 905324.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 418609 + 4900 = 647^2 + 70^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-423509 is a prime.

It is a Chen prime.

It is equal to p₃₅₆₆₃ and since 423509 and 35663 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (423503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 211754 + 211755.

It is an arithmetic number, because the mean of its divisors is an integer number (211755).

2⁴²³⁵⁰⁹ is an apocalyptic number.

It is an amenable number.

423509 is a deficient number, since it is larger than the sum of its proper divisors (1).

423509 is an equidigital number, since it uses as much as digits as its factorization.

423509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 423509 is about 650.7756910027. The cubic root of 423509 is about 75.0967048849.

The spelling of 423509 in words is "four hundred twenty-three thousand, five hundred nine".