666347 has 6 divisors (see below), whose sum is σ = 732564. Its totient is φ = 605660.

The previous prime is 666329. The next prime is 666353. The reversal of 666347 is 743666.

It is not a de Polignac number, because 666347 - 2⁸ = 666091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666647) 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 5 ways as a sum of consecutive naturals, for example, 2633 + ... + 2874.

It is an arithmetic number, because the mean of its divisors is an integer number (122094).

2⁶⁶⁶³⁴⁷ is an apocalyptic number.

666347 is a deficient number, since it is larger than the sum of its proper divisors (66217).

666347 is a wasteful number, since it uses less digits than its factorization.

666347 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5529 (or 5518 counting only the distinct ones).

The product of its digits is 18144, while the sum is 32.

The square root of 666347 is about 816.3008024007. The cubic root of 666347 is about 87.3440815136.

The spelling of 666347 in words is "six hundred sixty-six thousand, three hundred forty-seven".