778667787766877 has 2 divisors, whose sum is σ = 778667787766878. Its totient is φ = 778667787766876.

The previous prime is 778667787766871. The next prime is 778667787766879.

778667787766877 is nontrivially palindromic in base 10.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 472336372356601 + 306331415410276 = 21733301^2 + 17502326^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 778667787766877 - 2⁴ = 778667787766861 is a prime.

Together with 778667787766879, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (778667787766871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 389333893883438 + 389333893883439.

It is an arithmetic number, because the mean of its divisors is an integer number (389333893883439).

Almost surely, 2^{778667787766877} is an apocalyptic number.

It is an amenable number.

778667787766877 is a deficient number, since it is larger than the sum of its proper divisors (1).

778667787766877 is an equidigital number, since it uses as much as digits as its factorization.

778667787766877 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3825245233152, while the sum is 104.

The spelling of 778667787766877 in words is "seven hundred seventy-eight trillion, six hundred sixty-seven billion, seven hundred eighty-seven million, seven hundred sixty-six thousand, eight hundred seventy-seven".