209870393 has 2 divisors, whose sum is σ = 209870394. Its totient is φ = 209870392.

The previous prime is 209870363. The next prime is 209870411. The reversal of 209870393 is 393078902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 199713424 + 10156969 = 14132^2 + 3187^2 .

It is a cyclic number.

It is not a de Polignac number, because 209870393 - 2⁶ = 209870329 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 209870393.

It is not a weakly prime, because it can be changed into another prime (209870363) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104935196 + 104935197.

It is an arithmetic number, because the mean of its divisors is an integer number (104935197).

Almost surely, 2^209870393 is an apocalyptic number.

It is an amenable number.

209870393 is a deficient number, since it is larger than the sum of its proper divisors (1).

209870393 is an equidigital number, since it uses as much as digits as its factorization.

209870393 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81648, while the sum is 41.

The square root of 209870393 is about 14486.9041896466. The cubic root of 209870393 is about 594.2698885410.

The spelling of 209870393 in words is "two hundred nine million, eight hundred seventy thousand, three hundred ninety-three".