168539689 has 4 divisors (see below), whose sum is σ = 168568960. Its totient is φ = 168510420.

The previous prime is 168539681. The next prime is 168539719. The reversal of 168539689 is 986935861.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 986935861 = 79 ⋅12492859.

It is a cyclic number.

It is not a de Polignac number, because 168539689 - 2³ = 168539681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (168539681) 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, 2817 + ... + 18574.

It is an arithmetic number, because the mean of its divisors is an integer number (42142240).

Almost surely, 2^168539689 is an apocalyptic number.

It is an amenable number.

168539689 is a deficient number, since it is larger than the sum of its proper divisors (29271).

168539689 is an equidigital number, since it uses as much as digits as its factorization.

168539689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29270.

The product of its digits is 2799360, while the sum is 55.

The square root of 168539689 is about 12982.2836588945. The cubic root of 168539689 is about 552.3750612574.

The spelling of 168539689 in words is "one hundred sixty-eight million, five hundred thirty-nine thousand, six hundred eighty-nine".