666717 has 16 divisors (see below), whose sum is σ = 940032. Its totient is φ = 419760.

The previous prime is 666707. The next prime is 666727. The reversal of 666717 is 717666.

666717 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (666707) and next prime (666727).

It is not a de Polignac number, because 666717 - 2⁸ = 666461 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666707) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6178 + ... + 6284.

It is an arithmetic number, because the mean of its divisors is an integer number (58752).

2⁶⁶⁶⁷¹⁷ is an apocalyptic number.

666717 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

It is an amenable number.

666717 is a deficient number, since it is larger than the sum of its proper divisors (273315).

666717 is a wasteful number, since it uses less digits than its factorization.

666717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208.

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

The square root of 666717 is about 816.5274030919. The cubic root of 666717 is about 87.3602449291.

Multiplying 666717 by its sum of digits (33), we get a triangular number (22001661 = T₆₆₃₃).

The spelling of 666717 in words is "six hundred sixty-six thousand, seven hundred seventeen".