68681811643 has 2 divisors, whose sum is σ = 68681811644. Its totient is φ = 68681811642.

The previous prime is 68681811631. The next prime is 68681811691. The reversal of 68681811643 is 34611818686.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 68681811643 - 2¹³ = 68681803451 is a prime.

It is not a weakly prime, because it can be changed into another prime (68681811613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34340905821 + 34340905822.

It is an arithmetic number, because the mean of its divisors is an integer number (34340905822).

Almost surely, 2^68681811643 is an apocalyptic number.

68681811643 is a deficient number, since it is larger than the sum of its proper divisors (1).

68681811643 is an equidigital number, since it uses as much as digits as its factorization.

68681811643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1327104, while the sum is 52.

The spelling of 68681811643 in words is "sixty-eight billion, six hundred eighty-one million, eight hundred eleven thousand, six hundred forty-three".