66511701667 has 4 divisors (see below), whose sum is σ = 66514525560. Its totient is φ = 66508877776.

The previous prime is 66511701631. The next prime is 66511701671. The reversal of 66511701667 is 76610711566.

66511701667 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 66511701667 - 2⁷ = 66511701539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66511701167) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1376317 + ... + 1423822.

It is an arithmetic number, because the mean of its divisors is an integer number (16628631390).

Almost surely, 2^66511701667 is an apocalyptic number.

66511701667 is a deficient number, since it is larger than the sum of its proper divisors (2823893).

66511701667 is a wasteful number, since it uses less digits than its factorization.

66511701667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2823892.

The product of its (nonzero) digits is 317520, while the sum is 46.

The spelling of 66511701667 in words is "sixty-six billion, five hundred eleven million, seven hundred one thousand, six hundred sixty-seven".