664129171 has 2 divisors, whose sum is σ = 664129172. Its totient is φ = 664129170.

The previous prime is 664129159. The next prime is 664129177. The reversal of 664129171 is 171921466.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 664129171 - 2²³ = 655740563 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 664129171.

It is not a weakly prime, because it can be changed into another prime (664129177) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332064585 + 332064586.

It is an arithmetic number, because the mean of its divisors is an integer number (332064586).

Almost surely, 2^664129171 is an apocalyptic number.

664129171 is a deficient number, since it is larger than the sum of its proper divisors (1).

664129171 is an equidigital number, since it uses as much as digits as its factorization.

664129171 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18144, while the sum is 37.

The square root of 664129171 is about 25770.7037350554. The cubic root of 664129171 is about 872.4707022124.

The spelling of 664129171 in words is "six hundred sixty-four million, one hundred twenty-nine thousand, one hundred seventy-one".