666755 has 4 divisors (see below), whose sum is σ = 800112. Its totient is φ = 533400.

The previous prime is 666751. The next prime is 666769. The reversal of 666755 is 557666.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 666755 - 2² = 666751 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666751) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66671 + ... + 66680.

It is an arithmetic number, because the mean of its divisors is an integer number (200028).

2⁶⁶⁶⁷⁵⁵ is an apocalyptic number.

666755 is a deficient number, since it is larger than the sum of its proper divisors (133357).

666755 is a wasteful number, since it uses less digits than its factorization.

666755 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133356.

The product of its digits is 37800, while the sum is 35.

The square root of 666755 is about 816.5506720345. The cubic root of 666755 is about 87.3619046170.

The spelling of 666755 in words is "six hundred sixty-six thousand, seven hundred fifty-five".