78535919317 has 2 divisors, whose sum is σ = 78535919318. Its totient is φ = 78535919316.

The previous prime is 78535919309. The next prime is 78535919381. The reversal of 78535919317 is 71391953587.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50245015716 + 28290903601 = 224154^2 + 168199^2 .

It is a cyclic number.

It is not a de Polignac number, because 78535919317 - 2³ = 78535919309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78535979317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39267959658 + 39267959659.

It is an arithmetic number, because the mean of its divisors is an integer number (39267959659).

Almost surely, 2^78535919317 is an apocalyptic number.

It is an amenable number.

78535919317 is a deficient number, since it is larger than the sum of its proper divisors (1).

78535919317 is an equidigital number, since it uses as much as digits as its factorization.

78535919317 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7144200, while the sum is 58.

The spelling of 78535919317 in words is "seventy-eight billion, five hundred thirty-five million, nine hundred nineteen thousand, three hundred seventeen".