666071 has 4 divisors (see below), whose sum is σ = 761232. Its totient is φ = 570912.

The previous prime is 666067. The next prime is 666073. The reversal of 666071 is 170666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 170666 = 2 ⋅85333.

It is a cyclic number.

It is not a de Polignac number, because 666071 - 2² = 666067 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 666071.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47570 + ... + 47583.

It is an arithmetic number, because the mean of its divisors is an integer number (190308).

2⁶⁶⁶⁰⁷¹ is an apocalyptic number.

666071 is a deficient number, since it is larger than the sum of its proper divisors (95161).

666071 is an equidigital number, since it uses as much as digits as its factorization.

666071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95160.

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 666071 is about 816.1317295633. The cubic root of 666071 is about 87.3320205825.

The spelling of 666071 in words is "six hundred sixty-six thousand, seventy-one".