43686668681 has 2 divisors, whose sum is σ = 43686668682. Its totient is φ = 43686668680.

The previous prime is 43686668611. The next prime is 43686668693. The reversal of 43686668681 is 18686668634.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41581327225 + 2105341456 = 203915^2 + 45884^2 .

It is a cyclic number.

It is not a de Polignac number, because 43686668681 - 2¹⁸ = 43686406537 is a prime.

It is a super-2 number, since 2×43686668681² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (43686668611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21843334340 + 21843334341.

It is an arithmetic number, because the mean of its divisors is an integer number (21843334341).

Almost surely, 2^43686668681 is an apocalyptic number.

It is an amenable number.

43686668681 is a deficient number, since it is larger than the sum of its proper divisors (1).

43686668681 is an equidigital number, since it uses as much as digits as its factorization.

43686668681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47775744, while the sum is 62.

The spelling of 43686668681 in words is "forty-three billion, six hundred eighty-six million, six hundred sixty-eight thousand, six hundred eighty-one".