66766685 has 8 divisors (see below), whose sum is σ = 82285656. Its totient is φ = 51969600.

The previous prime is 66766681. The next prime is 66766691. The reversal of 66766685 is 58666766.

It can be written as a sum of positive squares in 4 ways, for example, as 24334489 + 42432196 = 4933^2 + 6514^2 .

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

It is not a de Polignac number, because 66766685 - 2² = 66766681 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66766681) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 180266 + ... + 180635.

It is an arithmetic number, because the mean of its divisors is an integer number (10285707).

Almost surely, 2^66766685 is an apocalyptic number.

It is an amenable number.

66766685 is a deficient number, since it is larger than the sum of its proper divisors (15518971).

66766685 is a wasteful number, since it uses less digits than its factorization.

66766685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360943.

The product of its digits is 2177280, while the sum is 50.

The square root of 66766685 is about 8171.0883607999. The cubic root of 66766685 is about 405.6828089510.

The spelling of 66766685 in words is "sixty-six million, seven hundred sixty-six thousand, six hundred eighty-five".