66687754779 has 12 divisors (see below), whose sum is σ = 99648369600. Its totient is φ = 42925451184.

The previous prime is 66687754769. The next prime is 66687754801. The reversal of 66687754779 is 97745778666.

It is a happy number.

It is not a de Polignac number, because 66687754779 - 2⁵ = 66687754747 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66687754769) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 127754059 + ... + 127754580.

It is an arithmetic number, because the mean of its divisors is an integer number (8304030800).

Almost surely, 2^66687754779 is an apocalyptic number.

66687754779 is a deficient number, since it is larger than the sum of its proper divisors (32960614821).

66687754779 is a wasteful number, since it uses less digits than its factorization.

66687754779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255508674 (or 255508671 counting only the distinct ones).

The product of its digits is 746807040, while the sum is 72.

The spelling of 66687754779 in words is "sixty-six billion, six hundred eighty-seven million, seven hundred fifty-four thousand, seven hundred seventy-nine".