66766686 has 16 divisors (see below), whose sum is σ = 152609664. Its totient is φ = 19076184.

The previous prime is 66766681. The next prime is 66766691. The reversal of 66766686 is 68666766.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (66766681) and next prime (66766691).

It is a Curzon 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, 794800 + ... + 794883.

It is an arithmetic number, because the mean of its divisors is an integer number (9538104).

Almost surely, 2^66766686 is an apocalyptic number.

66766686 is an abundant number, since it is smaller than the sum of its proper divisors (85842978).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66766686 is a wasteful number, since it uses less digits than its factorization.

66766686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1589695.

The product of its digits is 2612736, while the sum is 51.

The square root of 66766686 is about 8171.0884219913. The cubic root of 66766686 is about 405.6828109764.

The spelling of 66766686 in words is "sixty-six million, seven hundred sixty-six thousand, six hundred eighty-six".