66243866 has 16 divisors (see below), whose sum is σ = 113304744. Its totient is φ = 28775424.

The previous prime is 66243847. The next prime is 66243871. The reversal of 66243866 is 66834266.

It can be written as a sum of positive squares in 4 ways, for example, as 61293241 + 4950625 = 7829^2 + 2225^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74495 + ... + 75378.

Almost surely, 2^66243866 is an apocalyptic number.

66243866 is a deficient number, since it is larger than the sum of its proper divisors (47060878).

66243866 is a wasteful number, since it uses less digits than its factorization.

66243866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149905.

The product of its digits is 248832, while the sum is 41.

The square root of 66243866 is about 8139.0334807027. The cubic root of 66243866 is about 404.6211281788.

The spelling of 66243866 in words is "sixty-six million, two hundred forty-three thousand, eight hundred sixty-six".