609939409 has 2 divisors, whose sum is σ = 609939410. Its totient is φ = 609939408.

The previous prime is 609939403. The next prime is 609939431. The reversal of 609939409 is 904939906.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 423207184 + 186732225 = 20572^2 + 13665^2 .

It is a cyclic number.

It is not a de Polignac number, because 609939409 - 2³ = 609939401 is a prime.

It is not a weakly prime, because it can be changed into another prime (609939401) 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, 304969704 + 304969705.

It is an arithmetic number, because the mean of its divisors is an integer number (304969705).

Almost surely, 2^609939409 is an apocalyptic number.

It is an amenable number.

609939409 is a deficient number, since it is larger than the sum of its proper divisors (1).

609939409 is an equidigital number, since it uses as much as digits as its factorization.

609939409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 472392, while the sum is 49.

The square root of 609939409 is about 24696.9514110548. The cubic root of 609939409 is about 848.0645277118.

The spelling of 609939409 in words is "six hundred nine million, nine hundred thirty-nine thousand, four hundred nine".