78425317 has 2 divisors, whose sum is σ = 78425318. Its totient is φ = 78425316.

The previous prime is 78425261. The next prime is 78425327. The reversal of 78425317 is 71352487.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43744996 + 34680321 = 6614^2 + 5889^2 .

It is an emirp because it is prime and its reverse (71352487) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78425317 - 2⁷ = 78425189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78425327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39212658 + 39212659.

It is an arithmetic number, because the mean of its divisors is an integer number (39212659).

Almost surely, 2^78425317 is an apocalyptic number.

It is an amenable number.

78425317 is a deficient number, since it is larger than the sum of its proper divisors (1).

78425317 is an equidigital number, since it uses as much as digits as its factorization.

78425317 is an evil number, because the sum of its binary digits is even.

The product of its digits is 47040, while the sum is 37.

The square root of 78425317 is about 8855.8069649242. The cubic root of 78425317 is about 428.0410567800.

The spelling of 78425317 in words is "seventy-eight million, four hundred twenty-five thousand, three hundred seventeen".