77968686977 has 6 divisors (see below), whose sum is σ = 80749972758. Its totient is φ = 75280110752.

The previous prime is 77968686973. The next prime is 77968687019.

77968686977 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 3 ways, for example, as 33153490561 + 44815196416 = 182081^2 + 211696^2 .

It is not a de Polignac number, because 77968686977 - 2² = 77968686973 is a prime.

It is a super-2 number, since 2×77968686977² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77968686973) 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 5 ways as a sum of consecutive naturals, for example, 46353908 + ... + 46355589.

It is an arithmetic number, because the mean of its divisors is an integer number (13458328793).

Almost surely, 2^77968686977 is an apocalyptic number.

It is an amenable number.

77968686977 is a deficient number, since it is larger than the sum of its proper divisors (2781285781).

77968686977 is an equidigital number, since it uses as much as digits as its factorization.

77968686977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92709555 (or 92709526 counting only the distinct ones).

The product of its digits is 2688505344, while the sum is 80.

The spelling of 77968686977 in words is "seventy-seven billion, nine hundred sixty-eight million, six hundred eighty-six thousand, nine hundred seventy-seven".