77777788772777 has 2 divisors, whose sum is σ = 77777788772778. Its totient is φ = 77777788772776.

The previous prime is 77777788772693. The next prime is 77777788772791. The reversal of 77777788772777 is 77727788777777.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61043765928601 + 16734022844176 = 7813051^2 + 4090724^2 .

It is a cyclic number.

It is not a de Polignac number, because 77777788772777 - 2⁸ = 77777788772521 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 77777788772777.

It is not a weakly prime, because it can be changed into another prime (77777788772797) 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 as a sum of consecutive naturals, namely, 38888894386388 + 38888894386389.

It is an arithmetic number, because the mean of its divisors is an integer number (38888894386389).

Almost surely, 2^{77777788772777} is an apocalyptic number.

It is an amenable number.

77777788772777 is a deficient number, since it is larger than the sum of its proper divisors (1).

77777788772777 is an equidigital number, since it uses as much as digits as its factorization.

77777788772777 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 253097823104, while the sum is 95.

The spelling of 77777788772777 in words is "seventy-seven trillion, seven hundred seventy-seven billion, seven hundred eighty-eight million, seven hundred seventy-two thousand, seven hundred seventy-seven".