78481717 has 2 divisors, whose sum is σ = 78481718. Its totient is φ = 78481716.

The previous prime is 78481703. The next prime is 78481721. The reversal of 78481717 is 71718487.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76755121 + 1726596 = 8761^2 + 1314^2 .

It is a cyclic number.

It is not a de Polignac number, because 78481717 - 2¹¹ = 78479669 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78481217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39240858 + 39240859.

It is an arithmetic number, because the mean of its divisors is an integer number (39240859).

Almost surely, 2^78481717 is an apocalyptic number.

It is an amenable number.

78481717 is a deficient number, since it is larger than the sum of its proper divisors (1).

78481717 is an equidigital number, since it uses as much as digits as its factorization.

78481717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 87808, while the sum is 43.

The square root of 78481717 is about 8858.9907438714. The cubic root of 78481717 is about 428.1436415560.

The spelling of 78481717 in words is "seventy-eight million, four hundred eighty-one thousand, seven hundred seventeen".