666173 has 2 divisors, whose sum is σ = 666174. Its totient is φ = 666172.

The previous prime is 666167. The next prime is 666187. The reversal of 666173 is 371666.

It is a happy number.

666173 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 597529 + 68644 = 773^2 + 262^2 .

666173 is a truncatable prime.

It is a cyclic number.

It is not a de Polignac number, because 666173 - 2⁶ = 666109 is a prime.

It is a plaindrome in base 14.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333086 + 333087.

It is an arithmetic number, because the mean of its divisors is an integer number (333087).

2⁶⁶⁶¹⁷³ is an apocalyptic number.

It is an amenable number.

666173 is a deficient number, since it is larger than the sum of its proper divisors (1).

666173 is an equidigital number, since it uses as much as digits as its factorization.

666173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4536, while the sum is 29.

The square root of 666173 is about 816.1942170832. The cubic root of 666173 is about 87.3364782712.

The spelling of 666173 in words is "six hundred sixty-six thousand, one hundred seventy-three".