188931689 has 2 divisors, whose sum is σ = 188931690. Its totient is φ = 188931688.

The previous prime is 188931671. The next prime is 188931707. The reversal of 188931689 is 986139881.

It is a balanced prime because it is at equal distance from previous prime (188931671) and next prime (188931707).

It can be written as a sum of positive squares in only one way, i.e., 188595289 + 336400 = 13733^2 + 580^2 .

It is a cyclic number.

It is not a de Polignac number, because 188931689 - 2¹² = 188927593 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 188931689.

It is not a weakly prime, because it can be changed into another prime (188931619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94465844 + 94465845.

It is an arithmetic number, because the mean of its divisors is an integer number (94465845).

Almost surely, 2^188931689 is an apocalyptic number.

It is an amenable number.

188931689 is a deficient number, since it is larger than the sum of its proper divisors (1).

188931689 is an equidigital number, since it uses as much as digits as its factorization.

188931689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 746496, while the sum is 53.

The square root of 188931689 is about 13745.2424132861. The cubic root of 188931689 is about 573.8102066896.

The spelling of 188931689 in words is "one hundred eighty-eight million, nine hundred thirty-one thousand, six hundred eighty-nine".