78298390717 has 2 divisors, whose sum is σ = 78298390718. Its totient is φ = 78298390716.

The previous prime is 78298390673. The next prime is 78298390733. The reversal of 78298390717 is 71709389287.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68312185956 + 9986204761 = 261366^2 + 99931^2 .

It is an emirp because it is prime and its reverse (71709389287) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78298390717 - 2¹⁹ = 78297866429 is a prime.

It is a super-2 number, since 2×78298390717² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78298390777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39149195358 + 39149195359.

It is an arithmetic number, because the mean of its divisors is an integer number (39149195359).

Almost surely, 2^78298390717 is an apocalyptic number.

It is an amenable number.

78298390717 is a deficient number, since it is larger than the sum of its proper divisors (1).

78298390717 is an equidigital number, since it uses as much as digits as its factorization.

78298390717 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10668672, while the sum is 61.

The spelling of 78298390717 in words is "seventy-eight billion, two hundred ninety-eight million, three hundred ninety thousand, seven hundred seventeen".