77768486813 has 2 divisors, whose sum is σ = 77768486814. Its totient is φ = 77768486812.

The previous prime is 77768486749. The next prime is 77768486819. The reversal of 77768486813 is 31868486777.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43096929604 + 34671557209 = 207598^2 + 186203^2 .

It is a cyclic number.

It is not a de Polignac number, because 77768486813 - 2⁶ = 77768486749 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 77768486813.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77768486819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38884243406 + 38884243407.

It is an arithmetic number, because the mean of its divisors is an integer number (38884243407).

Almost surely, 2^77768486813 is an apocalyptic number.

It is an amenable number.

77768486813 is a deficient number, since it is larger than the sum of its proper divisors (1).

77768486813 is an equidigital number, since it uses as much as digits as its factorization.

77768486813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75866112, while the sum is 65.

The spelling of 77768486813 in words is "seventy-seven billion, seven hundred sixty-eight million, four hundred eighty-six thousand, eight hundred thirteen".