666375 has 16 divisors (see below), whose sum is σ = 1109472. Its totient is φ = 355200.

The previous prime is 666353. The next prime is 666403. The reversal of 666375 is 573666.

It is not a de Polignac number, because 666375 - 2⁸ = 666119 is a prime.

666375 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 514 + ... + 1263.

It is an arithmetic number, because the mean of its divisors is an integer number (69342).

2⁶⁶⁶³⁷⁵ is an apocalyptic number.

666375 is a deficient number, since it is larger than the sum of its proper divisors (443097).

666375 is a wasteful number, since it uses less digits than its factorization.

666375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1795 (or 1785 counting only the distinct ones).

The product of its digits is 22680, while the sum is 33.

The square root of 666375 is about 816.3179527611. The cubic root of 666375 is about 87.3453049002.

It can be divided in two parts, 66 and 6375, that added together give a triangular number (6441 = T₁₁₃).

The spelling of 666375 in words is "six hundred sixty-six thousand, three hundred seventy-five".