66648866 has 4 divisors (see below), whose sum is σ = 99973302. Its totient is φ = 33324432.

The previous prime is 66648859. The next prime is 66648887. The reversal of 66648866 is 66884666.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 43943641 + 22705225 = 6629^2 + 4765^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16662215 + ... + 16662218.

Almost surely, 2^66648866 is an apocalyptic number.

66648866 is a deficient number, since it is larger than the sum of its proper divisors (33324436).

66648866 is a wasteful number, since it uses less digits than its factorization.

66648866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33324435.

The product of its digits is 1990656, while the sum is 50.

The square root of 66648866 is about 8163.8756727427. The cubic root of 66648866 is about 405.4440407423. Note that the first 3 decimals are identical.

The spelling of 66648866 in words is "sixty-six million, six hundred forty-eight thousand, eight hundred sixty-six".