666771 has 8 divisors (see below), whose sum is σ = 1016064. Its totient is φ = 381000.

The previous prime is 666769. The next prime is 666773. The reversal of 666771 is 177666.

It is an interprime number because it is at equal distance from previous prime (666769) and next prime (666773).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 666771 - 2¹ = 666769 is a prime.

It is a plaindrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666773) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15855 + ... + 15896.

It is an arithmetic number, because the mean of its divisors is an integer number (127008).

2⁶⁶⁶⁷⁷¹ is an apocalyptic number.

666771 is a deficient number, since it is larger than the sum of its proper divisors (349293).

666771 is a wasteful number, since it uses less digits than its factorization.

666771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31761.

The product of its digits is 10584, while the sum is 33.

The square root of 666771 is about 816.5604692856. The cubic root of 666771 is about 87.3626034140.

The spelling of 666771 in words is "six hundred sixty-six thousand, seven hundred seventy-one".