66799648847 has 4 divisors (see below), whose sum is σ = 66816944880. Its totient is φ = 66782352816.

The previous prime is 66799648841. The next prime is 66799648897. The reversal of 66799648847 is 74884699766.

66799648847 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 66799648847 - 2²² = 66795454543 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66799648841) 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, 8642222 + ... + 8649947.

It is an arithmetic number, because the mean of its divisors is an integer number (16704236220).

Almost surely, 2^66799648847 is an apocalyptic number.

66799648847 is a deficient number, since it is larger than the sum of its proper divisors (17296033).

66799648847 is a wasteful number, since it uses less digits than its factorization.

66799648847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17296032.

The product of its digits is 877879296, while the sum is 74.

The spelling of 66799648847 in words is "sixty-six billion, seven hundred ninety-nine million, six hundred forty-eight thousand, eight hundred forty-seven".