666758 has 8 divisors (see below), whose sum is σ = 1023528. Its totient is φ = 325584.

The previous prime is 666751. The next prime is 666769. The reversal of 666758 is 857666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an Ulam number.

It is a congruent 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, 3791 + ... + 3962.

It is an arithmetic number, because the mean of its divisors is an integer number (127941).

2⁶⁶⁶⁷⁵⁸ is an apocalyptic number.

666758 is a deficient number, since it is larger than the sum of its proper divisors (356770).

666758 is a wasteful number, since it uses less digits than its factorization.

666758 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7798.

The product of its digits is 60480, while the sum is 38.

The square root of 666758 is about 816.5525090280. The cubic root of 666758 is about 87.3620356423.

The spelling of 666758 in words is "six hundred sixty-six thousand, seven hundred fifty-eight".