66647074666 has 4 divisors (see below), whose sum is σ = 99970612002. Its totient is φ = 33323537332.

The previous prime is 66647074661. The next prime is 66647074709.

66647074666 is nontrivially palindromic in base 10.

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., 57712855225 + 8934219441 = 240235^2 + 94521^2 .

It is a super-3 number, since 3×66647074666³ (a number of 33 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 66647074666.

It is not an unprimeable number, because it can be changed into a prime (66647074661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16661768665 + ... + 16661768668.

Almost surely, 2^66647074666 is an apocalyptic number.

66647074666 is a deficient number, since it is larger than the sum of its proper divisors (33323537336).

66647074666 is a wasteful number, since it uses less digits than its factorization.

66647074666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33323537335.

The product of its (nonzero) digits is 36578304, while the sum is 58.

The spelling of 66647074666 in words is "sixty-six billion, six hundred forty-seven million, seventy-four thousand, six hundred sixty-six".