68401643617 has 2 divisors, whose sum is σ = 68401643618. Its totient is φ = 68401643616.

The previous prime is 68401643549. The next prime is 68401643621. The reversal of 68401643617 is 71634610486.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62679628881 + 5722014736 = 250359^2 + 75644^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68401643617 is a prime.

It is not a weakly prime, because it can be changed into another prime (68401643917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34200821808 + 34200821809.

It is an arithmetic number, because the mean of its divisors is an integer number (34200821809).

Almost surely, 2^68401643617 is an apocalyptic number.

It is an amenable number.

68401643617 is a deficient number, since it is larger than the sum of its proper divisors (1).

68401643617 is an equidigital number, since it uses as much as digits as its factorization.

68401643617 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 580608, while the sum is 46.

The spelling of 68401643617 in words is "sixty-eight billion, four hundred one million, six hundred forty-three thousand, six hundred seventeen".