609181609 has 2 divisors, whose sum is σ = 609181610. Its totient is φ = 609181608.

The previous prime is 609181607. The next prime is 609181663. The reversal of 609181609 is 906181906.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 492973209 + 116208400 = 22203^2 + 10780^2 .

It is a cyclic number.

It is not a de Polignac number, because 609181609 - 2¹ = 609181607 is a prime.

It is a super-2 number, since 2×609181609² = 742204465487657762, which contains 22 as substring.

Together with 609181607, it forms a pair of twin primes.

609181609 is a strobogrammatic number because it is the same when read upside-down.

It is not a weakly prime, because it can be changed into another prime (609181607) 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, 304590804 + 304590805.

It is an arithmetic number, because the mean of its divisors is an integer number (304590805).

Almost surely, 2^609181609 is an apocalyptic number.

It is an amenable number.

609181609 is a deficient number, since it is larger than the sum of its proper divisors (1).

609181609 is an equidigital number, since it uses as much as digits as its factorization.

609181609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 40.

The square root of 609181609 is about 24681.6046682545. The cubic root of 609181609 is about 847.7131651416.

The spelling of 609181609 in words is "six hundred nine million, one hundred eighty-one thousand, six hundred nine".