188961609 has 4 divisors (see below), whose sum is σ = 251948816. Its totient is φ = 125974404.

The previous prime is 188961599. The next prime is 188961671. The reversal of 188961609 is 906169881.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 188961609 - 2¹² = 188957513 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (188961209) 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 in 3 ways as a sum of consecutive naturals, for example, 31493599 + ... + 31493604.

It is an arithmetic number, because the mean of its divisors is an integer number (62987204).

Almost surely, 2^188961609 is an apocalyptic number.

It is an amenable number.

188961609 is a deficient number, since it is larger than the sum of its proper divisors (62987207).

188961609 is an equidigital number, since it uses as much as digits as its factorization.

188961609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62987206.

The product of its (nonzero) digits is 186624, while the sum is 48.

The square root of 188961609 is about 13746.3307467848. The cubic root of 188961609 is about 573.8404954063.

The spelling of 188961609 in words is "one hundred eighty-eight million, nine hundred sixty-one thousand, six hundred nine".