66778287766 has 32 divisors (see below), whose sum is σ = 104012366976. Its totient is φ = 32132160000.

The previous prime is 66778287757. The next prime is 66778287781.

66778287766 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 66778287695 and 66778287704.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2229546 + ... + 2259298.

It is an arithmetic number, because the mean of its divisors is an integer number (3250386468).

Almost surely, 2^66778287766 is an apocalyptic number.

66778287766 is a deficient number, since it is larger than the sum of its proper divisors (37234079210).

66778287766 is a wasteful number, since it uses less digits than its factorization.

66778287766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30168.

The product of its digits is 398297088, while the sum is 70.

The spelling of 66778287766 in words is "sixty-six billion, seven hundred seventy-eight million, two hundred eighty-seven thousand, seven hundred sixty-six".