78885412087217 has 2 divisors, whose sum is σ = 78885412087218. Its totient is φ = 78885412087216.

The previous prime is 78885412087211. The next prime is 78885412087253. The reversal of 78885412087217 is 71278021458887.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44281358771776 + 34604053315441 = 6654424^2 + 5882521^2 .

It is a cyclic number.

It is not a de Polignac number, because 78885412087217 - 2¹⁰ = 78885412086193 is a prime.

It is not a weakly prime, because it can be changed into another prime (78885412087211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39442706043608 + 39442706043609.

It is an arithmetic number, because the mean of its divisors is an integer number (39442706043609).

Almost surely, 2^{78885412087217} is an apocalyptic number.

It is an amenable number.

78885412087217 is a deficient number, since it is larger than the sum of its proper divisors (1).

78885412087217 is an equidigital number, since it uses as much as digits as its factorization.

78885412087217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112394240, while the sum is 68.

The spelling of 78885412087217 in words is "seventy-eight trillion, eight hundred eighty-five billion, four hundred twelve million, eighty-seven thousand, two hundred seventeen".