67868920681 has 2 divisors, whose sum is σ = 67868920682. Its totient is φ = 67868920680.

The previous prime is 67868920673. The next prime is 67868920687. The reversal of 67868920681 is 18602986876.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48013574400 + 19855346281 = 219120^2 + 140909^2 .

It is a cyclic number.

It is not a de Polignac number, because 67868920681 - 2³ = 67868920673 is a prime.

It is a super-2 number, since 2×67868920681² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (67868920687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33934460340 + 33934460341.

It is an arithmetic number, because the mean of its divisors is an integer number (33934460341).

Almost surely, 2^67868920681 is an apocalyptic number.

It is an amenable number.

67868920681 is a deficient number, since it is larger than the sum of its proper divisors (1).

67868920681 is an equidigital number, since it uses as much as digits as its factorization.

67868920681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13934592, while the sum is 61.

The spelling of 67868920681 in words is "sixty-seven billion, eight hundred sixty-eight million, nine hundred twenty thousand, six hundred eighty-one".