209389423 has 2 divisors, whose sum is σ = 209389424. Its totient is φ = 209389422.

The previous prime is 209389399. The next prime is 209389429. The reversal of 209389423 is 324983902.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 209389423 - 2¹⁷ = 209258351 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (209389429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104694711 + 104694712.

It is an arithmetic number, because the mean of its divisors is an integer number (104694712).

Almost surely, 2^209389423 is an apocalyptic number.

209389423 is a deficient number, since it is larger than the sum of its proper divisors (1).

209389423 is an equidigital number, since it uses as much as digits as its factorization.

209389423 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 93312, while the sum is 40.

The square root of 209389423 is about 14470.2945028773. The cubic root of 209389423 is about 593.8155690764.

The spelling of 209389423 in words is "two hundred nine million, three hundred eighty-nine thousand, four hundred twenty-three".