66599778683 has 4 divisors (see below), whose sum is σ = 66616110240. Its totient is φ = 66583447128.

The previous prime is 66599778607. The next prime is 66599778689. The reversal of 66599778683 is 38687799566.

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 66599778683 - 2²² = 66595584379 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66599778683.

It is not an unprimeable number, because it can be changed into a prime (66599778689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8159660 + ... + 8167817.

It is an arithmetic number, because the mean of its divisors is an integer number (16654027560).

Almost surely, 2^66599778683 is an apocalyptic number.

66599778683 is a deficient number, since it is larger than the sum of its proper divisors (16331557).

66599778683 is a wasteful number, since it uses less digits than its factorization.

66599778683 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16331556.

The product of its digits is 823011840, while the sum is 74.

The spelling of 66599778683 in words is "sixty-six billion, five hundred ninety-nine million, seven hundred seventy-eight thousand, six hundred eighty-three".