68209778893 has 2 divisors, whose sum is σ = 68209778894. Its totient is φ = 68209778892.

The previous prime is 68209778887. The next prime is 68209778951. The reversal of 68209778893 is 39887790286.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68135094729 + 74684164 = 261027^2 + 8642^2 .

It is a cyclic number.

It is not a de Polignac number, because 68209778893 - 2⁹ = 68209778381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68209778803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34104889446 + 34104889447.

It is an arithmetic number, because the mean of its divisors is an integer number (34104889447).

Almost surely, 2^68209778893 is an apocalyptic number.

It is an amenable number.

68209778893 is a deficient number, since it is larger than the sum of its proper divisors (1).

68209778893 is an equidigital number, since it uses as much as digits as its factorization.

68209778893 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 73156608, while the sum is 67.

The spelling of 68209778893 in words is "sixty-eight billion, two hundred nine million, seven hundred seventy-eight thousand, eight hundred ninety-three".