66868086869 has 2 divisors, whose sum is σ = 66868086870. Its totient is φ = 66868086868.

The previous prime is 66868086851. The next prime is 66868086877. The reversal of 66868086869 is 96868086866.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 36151318225 + 30716768644 = 190135^2 + 175262^2 .

It is a cyclic number.

It is not a de Polignac number, because 66868086869 - 2⁸ = 66868086613 is a prime.

It is a super-2 number, since 2×66868086869² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66868086839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33434043434 + 33434043435.

It is an arithmetic number, because the mean of its divisors is an integer number (33434043435).

Almost surely, 2^66868086869 is an apocalyptic number.

It is an amenable number.

66868086869 is a deficient number, since it is larger than the sum of its proper divisors (1).

66868086869 is an equidigital number, since it uses as much as digits as its factorization.

66868086869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 286654464, while the sum is 71.

The spelling of 66868086869 in words is "sixty-six billion, eight hundred sixty-eight million, eighty-six thousand, eight hundred sixty-nine".