668500171 has 2 divisors, whose sum is σ = 668500172. Its totient is φ = 668500170.

The previous prime is 668500081. The next prime is 668500207. The reversal of 668500171 is 171005866.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 668500171 - 2¹³ = 668491979 is a prime.

It is equal to p_34704691 and since 668500171 and 34704691 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (668500871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334250085 + 334250086.

It is an arithmetic number, because the mean of its divisors is an integer number (334250086).

Almost surely, 2^668500171 is an apocalyptic number.

668500171 is a deficient number, since it is larger than the sum of its proper divisors (1).

668500171 is an equidigital number, since it uses as much as digits as its factorization.

668500171 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 668500171 is about 25855.3702545525. The cubic root of 668500171 is about 874.3805884526.

The spelling of 668500171 in words is "six hundred sixty-eight million, five hundred thousand, one hundred seventy-one".