666417 has 16 divisors (see below), whose sum is σ = 959040. Its totient is φ = 410112.

The previous prime is 666403. The next prime is 666427. The reversal of 666417 is 714666.

It is not a de Polignac number, because 666417 - 2⁶ = 666353 is a prime.

It is a super-2 number, since 2×666417² = 888223235778, which contains 22 as substring.

666417 is a lucky number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 666417.

It is not an unprimeable number, because it can be changed into a prime (666427) 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, 3634 + ... + 3812.

It is an arithmetic number, because the mean of its divisors is an integer number (59940).

2⁶⁶⁶⁴¹⁷ is an apocalyptic number.

It is an amenable number.

666417 is a deficient number, since it is larger than the sum of its proper divisors (292623).

666417 is a wasteful number, since it uses less digits than its factorization.

666417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272.

The product of its digits is 6048, while the sum is 30.

The square root of 666417 is about 816.3436776260. The cubic root of 666417 is about 87.3471399159.

The spelling of 666417 in words is "six hundred sixty-six thousand, four hundred seventeen".