78817698697 has 2 divisors, whose sum is σ = 78817698698. Its totient is φ = 78817698696.

The previous prime is 78817698683. The next prime is 78817698709. The reversal of 78817698697 is 79689671887.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75987884281 + 2829814416 = 275659^2 + 53196^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78817698697 is a prime.

It is not a weakly prime, because it can be changed into another prime (78817698797) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39408849348 + 39408849349.

It is an arithmetic number, because the mean of its divisors is an integer number (39408849349).

Almost surely, 2^78817698697 is an apocalyptic number.

It is an amenable number.

78817698697 is a deficient number, since it is larger than the sum of its proper divisors (1).

78817698697 is an equidigital number, since it uses as much as digits as its factorization.

78817698697 is an evil number, because the sum of its binary digits is even.

The product of its digits is 512096256, while the sum is 76.

The spelling of 78817698697 in words is "seventy-eight billion, eight hundred seventeen million, six hundred ninety-eight thousand, six hundred ninety-seven".