68781308591 has 2 divisors, whose sum is σ = 68781308592. Its totient is φ = 68781308590.

The previous prime is 68781308551. The next prime is 68781308633. The reversal of 68781308591 is 19580318786.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 68781308591 - 2⁶ = 68781308527 is a prime.

It is a super-2 number, since 2×68781308591² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68781308501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34390654295 + 34390654296.

It is an arithmetic number, because the mean of its divisors is an integer number (34390654296).

Almost surely, 2^68781308591 is an apocalyptic number.

68781308591 is a deficient number, since it is larger than the sum of its proper divisors (1).

68781308591 is an equidigital number, since it uses as much as digits as its factorization.

68781308591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2903040, while the sum is 56.

The spelling of 68781308591 in words is "sixty-eight billion, seven hundred eighty-one million, three hundred eight thousand, five hundred ninety-one".