78568740821663 has 2 divisors, whose sum is σ = 78568740821664. Its totient is φ = 78568740821662.

The previous prime is 78568740821621. The next prime is 78568740821717. The reversal of 78568740821663 is 36612804786587.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78568740821663 - 2⁸ = 78568740821407 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78568740721663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39284370410831 + 39284370410832.

It is an arithmetic number, because the mean of its divisors is an integer number (39284370410832).

Almost surely, 2^{78568740821663} is an apocalyptic number.

78568740821663 is a deficient number, since it is larger than the sum of its proper divisors (1).

78568740821663 is an equidigital number, since it uses as much as digits as its factorization.

78568740821663 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 650280960, while the sum is 71.

The spelling of 78568740821663 in words is "seventy-eight trillion, five hundred sixty-eight billion, seven hundred forty million, eight hundred twenty-one thousand, six hundred sixty-three".