168709817719 has 4 divisors (see below), whose sum is σ = 172633301896. Its totient is φ = 164786333544.

The previous prime is 168709817699. The next prime is 168709817747. The reversal of 168709817719 is 917718907861.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-168709817719 is a prime.

It is a super-2 number, since 2×168709817719² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168709817219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1961742024 + ... + 1961742109.

It is an arithmetic number, because the mean of its divisors is an integer number (43158325474).

Almost surely, 2^168709817719 is an apocalyptic number.

168709817719 is a deficient number, since it is larger than the sum of its proper divisors (3923484177).

168709817719 is an equidigital number, since it uses as much as digits as its factorization.

168709817719 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3923484176.

The product of its (nonzero) digits is 10668672, while the sum is 64.

The spelling of 168709817719 in words is "one hundred sixty-eight billion, seven hundred nine million, eight hundred seventeen thousand, seven hundred nineteen".