78810287893 has 2 divisors, whose sum is σ = 78810287894. Its totient is φ = 78810287892.

The previous prime is 78810287887. The next prime is 78810287909. The reversal of 78810287893 is 39878201887.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71426838564 + 7383449329 = 267258^2 + 85927^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78810287893 is a prime.

It is a super-2 number, since 2×78810287893² (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 (78810287873) 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, 39405143946 + 39405143947.

It is an arithmetic number, because the mean of its divisors is an integer number (39405143947).

Almost surely, 2^78810287893 is an apocalyptic number.

It is an amenable number.

78810287893 is a deficient number, since it is larger than the sum of its proper divisors (1).

78810287893 is an equidigital number, since it uses as much as digits as its factorization.

78810287893 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10838016, while the sum is 61.

The spelling of 78810287893 in words is "seventy-eight billion, eight hundred ten million, two hundred eighty-seven thousand, eight hundred ninety-three".