66766864 has 10 divisors (see below), whose sum is σ = 129360830. Its totient is φ = 33383424.

The previous prime is 66766859. The next prime is 66766867. The reversal of 66766864 is 46866766.

It can be written as a sum of positive squares in only one way, i.e., 60715264 + 6051600 = 7792^2 + 2460^2 .

It is not an unprimeable number, because it can be changed into a prime (66766867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2086449 + ... + 2086480.

It is an arithmetic number, because the mean of its divisors is an integer number (12936083).

Almost surely, 2^66766864 is an apocalyptic number.

It is an amenable number.

66766864 is a deficient number, since it is larger than the sum of its proper divisors (62593966).

66766864 is a wasteful number, since it uses less digits than its factorization.

66766864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4172937 (or 4172931 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 49.

The square root of 66766864 is about 8171.0993140458. The cubic root of 66766864 is about 405.6831714929.

The spelling of 66766864 in words is "sixty-six million, seven hundred sixty-six thousand, eight hundred sixty-four".