188609 has 2 divisors, whose sum is σ = 188610. Its totient is φ = 188608.

The previous prime is 188603. The next prime is 188621. The reversal of 188609 is 906881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 172225 + 16384 = 415^2 + 128^2 .

It is an emirp because it is prime and its reverse (906881) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-188609 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (188603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94304 + 94305.

It is an arithmetic number, because the mean of its divisors is an integer number (94305).

2¹⁸⁸⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

188609 is a deficient number, since it is larger than the sum of its proper divisors (1).

188609 is an equidigital number, since it uses as much as digits as its factorization.

188609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 188609 is about 434.2913768428. The cubic root of 188609 is about 57.3483337651.

It can be divided in two parts, 188 and 609, that added together give a palindrome (797).

The spelling of 188609 in words is "one hundred eighty-eight thousand, six hundred nine".