66817171 has 2 divisors, whose sum is σ = 66817172. Its totient is φ = 66817170.

The previous prime is 66817133. The next prime is 66817187. The reversal of 66817171 is 17171866.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66817171 - 2¹³ = 66808979 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66817171.

It is not a weakly prime, because it can be changed into another prime (66817111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33408585 + 33408586.

It is an arithmetic number, because the mean of its divisors is an integer number (33408586).

Almost surely, 2^66817171 is an apocalyptic number.

66817171 is a deficient number, since it is larger than the sum of its proper divisors (1).

66817171 is an equidigital number, since it uses as much as digits as its factorization.

66817171 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14112, while the sum is 37.

The square root of 66817171 is about 8174.1770839639. The cubic root of 66817171 is about 405.7850362924.

The spelling of 66817171 in words is "sixty-six million, eight hundred seventeen thousand, one hundred seventy-one".