171968518 has 4 divisors (see below), whose sum is σ = 257952780. Its totient is φ = 85984258.

The previous prime is 171968513. The next prime is 171968519. The reversal of 171968518 is 815869171.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 815869171 = 13 ⋅62759167.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (171968513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42992128 + ... + 42992131.

It is an arithmetic number, because the mean of its divisors is an integer number (64488195).

Almost surely, 2^171968518 is an apocalyptic number.

171968518 is a deficient number, since it is larger than the sum of its proper divisors (85984262).

171968518 is an equidigital number, since it uses as much as digits as its factorization.

171968518 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85984261.

The product of its digits is 120960, while the sum is 46.

The square root of 171968518 is about 13113.6767536797. The cubic root of 171968518 is about 556.0958441988.

The spelling of 171968518 in words is "one hundred seventy-one million, nine hundred sixty-eight thousand, five hundred eighteen".