77778516315823 has 2 divisors, whose sum is σ = 77778516315824. Its totient is φ = 77778516315822.

The previous prime is 77778516315809. The next prime is 77778516315911. The reversal of 77778516315823 is 32851361587777.

It is a weak prime.

It is an emirp because it is prime and its reverse (32851361587777) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77778516315823 - 2⁵ = 77778516315791 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77778516375823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38889258157911 + 38889258157912.

It is an arithmetic number, because the mean of its divisors is an integer number (38889258157912).

Almost surely, 2^{77778516315823} is an apocalyptic number.

77778516315823 is a deficient number, since it is larger than the sum of its proper divisors (1).

77778516315823 is an equidigital number, since it uses as much as digits as its factorization.

77778516315823 is an evil number, because the sum of its binary digits is even.

The product of its digits is 414892800, while the sum is 70.

The spelling of 77778516315823 in words is "seventy-seven trillion, seven hundred seventy-eight billion, five hundred sixteen million, three hundred fifteen thousand, eight hundred twenty-three".