78857681093 has 2 divisors, whose sum is σ = 78857681094. Its totient is φ = 78857681092.

The previous prime is 78857681083. The next prime is 78857681101. The reversal of 78857681093 is 39018675887.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46283928769 + 32573752324 = 215137^2 + 180482^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78857681093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78857681003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39428840546 + 39428840547.

It is an arithmetic number, because the mean of its divisors is an integer number (39428840547).

Almost surely, 2^78857681093 is an apocalyptic number.

It is an amenable number.

78857681093 is a deficient number, since it is larger than the sum of its proper divisors (1).

78857681093 is an equidigital number, since it uses as much as digits as its factorization.

78857681093 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20321280, while the sum is 62.

The spelling of 78857681093 in words is "seventy-eight billion, eight hundred fifty-seven million, six hundred eighty-one thousand, ninety-three".