163

163 is the 38th prime number and a strong prime in the sense that it is greater than the arithmetic mean of its two neighboring primes. 163 is a lucky prime and a fortunate number. 163 is a strictly non-palindromic number, since it is not palindromic in any base between base 2 and base 161. Given 163, the Mertens function returns 0, it is the fourth prime with this property, the first three such primes are 2, 101 and 149. As approximations, π ≈ 2 9 163 ≈ 3.1411... {\displaystyle \pi \approx {2^{9} \over 163}\approx 3.1411...}, and e ≈ 163 3 ⋅ 4 ⋅ 5 ≈ 2.7166 … {\displaystyle e\approx {163 \over 3\cdot 4\cdot 5}\approx 2.7166\dots }