68051385806681 has 2 divisors, whose sum is σ = 68051385806682. Its totient is φ = 68051385806680.

The previous prime is 68051385806647. The next prime is 68051385806689. The reversal of 68051385806681 is 18660858315086.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48727589665225 + 19323796141456 = 6980515^2 + 4395884^2 .

It is a cyclic number.

It is not a de Polignac number, because 68051385806681 - 2¹⁸ = 68051385544537 is a prime.

It is a super-2 number, since 2×68051385806681² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (68051385806689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34025692903340 + 34025692903341.

It is an arithmetic number, because the mean of its divisors is an integer number (34025692903341).

Almost surely, 2^{68051385806681} is an apocalyptic number.

It is an amenable number.

68051385806681 is a deficient number, since it is larger than the sum of its proper divisors (1).

68051385806681 is an equidigital number, since it uses as much as digits as its factorization.

68051385806681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 66355200, while the sum is 65.

The spelling of 68051385806681 in words is "sixty-eight trillion, fifty-one billion, three hundred eighty-five million, eight hundred six thousand, six hundred eighty-one".